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VALIDATION OF THE COREDRYTM AND COREREADERTM APPRATUS By GYANENDRA POKHREL Bachelor of Science in Civil Engineering Nepal Engineering College Bhaktapur, Nepal 2004 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE December, 2007 i i VALIDATION OF THE COREDRYTM AND COREREADERTM APPRATUS Thesis Approved: Dr. Stephen A. Cross Thesis Adviser Dr. Rifat Bulut Dr. Hyung Seok(David) Jeong Dr. A. Gordon Emslie Dean of the Graduate College ii i TABLE OF CONTENTS Chapter Page 1. INTRODUCTION .....................................................................................................1 PROBLEM STATEMENT......................................................................................1 OBJECTIVES..........................................................................................................2 SCOPE.....................................................................................................................3 2. REVIEW OF LITERATURE………………………………………………………4 BULK SPECIFIC GRAVITY OF ASPHALT MIXES (Gmb) ...............................4 AASHTO T166........................................................................................................5 Method A ..............................................................................................................5 Method B ..............................................................................................................5 Method C ..............................................................................................................6 ASTM D2726...........................................................................................................6 COREDRYTM ..........................................................................................................7 COREREADERTM...................................................................................................9 PREVIOUS RESEARCH......................................................................................11 CoreDryTM............................................................................................................11 CoreReaderTM ......................................................................................................13 SUMMARY...........................................................................................................14 3. TEST PLAN……………………………………………………………………….15 MATERIALS.........................................................................................................15 Lab Samples.........................................................................................................15 S3 and S4 Mixes ................................................................................................16 Stone Matrix Asphalt (SMA) Mix .....................................................................17 Field Cores ...........................................................................................................18 TEST PROCEDURE .............................................................................................19 Lab Samples ........................................................................................................19 Group A ...........................................................................................................20 Group B.............................................................................................................20 Field Cores ...........................................................................................................21 Effect of Parallel Faces ........................................................................................22 Before Sawing....................................................................................................22 After Sawing ......................................................................................................22 ANALYSIS............................................................................................................24 iv Phase I CoreDryTM.............................................................................................24 Phase II CoreReaderTM ......................................................................................24 Phase III .............................................................................................................24 4. TEST RESULTS......................................................................................................25 PHASE I COREDRYTM ........................................................................................25 Group A ...............................................................................................................26 Group B................................................................................................................26 PHASE II COREREADERTM................................................................................27 PHASE III ..............................................................................................................27 5. ANALYSIS OF TEST RESULTS..........................................................................47 PHASE I COREDRYTM ........................................................................................47 ANOVA with Duncan’s Test...............................................................................48 Lab Compacted Samples..................................................................................48 Field Cores .......................................................................................................52 Paired tTest .........................................................................................................55 Lab Compacted Samples...................................................................................55 Field Cores ........................................................................................................56 Practical Significance...........................................................................................57 Lab Compacted Samples...................................................................................57 Field Cores ........................................................................................................58 PHASE II COREREADERTM................................................................................59 ANOVA with Duncan’s Test...............................................................................60 Lab Compacted Samples..................................................................................60 Field Cores .......................................................................................................62 Paired tTest .........................................................................................................63 Lab Compacted Samples...................................................................................63 Field Cores ........................................................................................................64 Practical Significance...........................................................................................65 Lab Compacted Samples...................................................................................65 Field Cores ........................................................................................................66 PHASE III ..............................................................................................................67 Effect of Parallel Faces on CoreReaderTM Gmb...............................................67 CORRELATION BETWEEN COREREADERTMAND AASHTO T166 Gmb ...69 Lab Compacted Samples..................................................................................69 Field Cores .......................................................................................................71 6. CONCLUSIONS AND RECOMMENDATIONS ..................................................72 CONCLUSIONS....................................................................................................72 Phase I CoreDryTM..............................................................................................72 Phase II CoreReaderTM .......................................................................................73 Phase III Effect of Parallel Faces on CoreReaderTM Gmb..................................73 v RECOMMENDATIONS.......................................................................................74 REFERENCES ............................................................................................................75 vi LIST OF TABLES Table Page 3.1. Test Specimens of S3 and S4 Mix .....................................................................15 3.2. S3 and S4 Mix Design .......................................................................................16 3.3. Typical Gradation of Aggregate for SMA.........................................................18 4.1. Lab Test Result of Lab Compacted Samples, Phase I, Group A ......................28 4.2. Lab Test Result of Field Cores, Phase I, Group A ............................................29 4.3. Lab Test Result of Lab Compacted Samples, Phase I, Group B ......................32 4.4. Lab Test Result of Field Cores, Phase I, Group B.............................................33 4.5. Lab Test Result of Lab Compacted Samples, Phase II, Group A .....................37 4.6. Lab Test Result of Field Cores, Phase II, Group A ..........................................38 4.7. Lab Test Result of Lab Compacted Samples, Phase II, Group B .....................41 4.8. Lab Test Result of Field Cores, Phase II, Group B ...........................................42 4.9. CoreReaderTM Gmb Before and After Sawing of Field Cores ..........................45 5.1. ANOVA Test Results, Group A, Height= 95 mm, (By Height)........................49 5.2. ANOVA Test Results, Group A, Height= 115 mm, (By Height)......................49 5.3. ANOVA Test Results, Group B, Height= 95 mm, (By Height) ........................49 5.4. ANOVA Test Results, Group B, Height= 115 mm, (By Height) ......................50 5.5. ANOVA Test Results for Field Cores, Group A, (By Group)...........................53 5.6. ANOVA Test Results for Field Cores, Group B, (By Group)...........................53 5.7. Paired ttest Result for Lab Compacted Samples ..............................................56 5.8. Paired ttest Result for Field Core Samples.......................................................57 5.9. Practical Significance of the Test Result for Lab Compacted Samples.............58 5.10. Practical Significance of the Test Result for Field Cores ...............................59 5.11. ANOVA Test Results for Lab Compacted Samples, Group A, (By Group) ...61 5.12. ANOVA Test Results for Lab Compacted Samples, Group B, (By Group) ...61 5.13. ANOVA Test Results for Field Cores, Group A, (By Group).........................62 5.14. ANOVA Test Results for Field Cores, Group B, (By Group).........................63 5.15. Paired ttest Results for Lab Compacted Samples ..........................................64 5.16. Paired ttest Results for Field Core Samples ...................................................65 5.17. Practical Significance of the Test Result for Lab Compacted Samples...........66 5.18. Practical Significance of the Test Result for Field Core Samples ...................67 5.19. ttest Results for the Effect of Parallel Faces on CoreReaderTM Gmb.............68 vii LIST OF FIGURES Figure Page 2.1 InstroTek® CoreDryTM apparatus............................................................................8 2.2 Troxler CoreReaderTM Model 3660.......................................................................10 3.1 Grain size distribution curve of aggregate for S3 and S4 mixes............................17 3.2 Typical grain size distribution curve for SMA mix...............................................18 3.3 Test procedure for lab compacted samples ............................................................21 3.4 Test procedure for field core samples ....................................................................23 5.1 Interval plot for lab compacted samples (Group A) ..............................................51 5.2 Interval plot for lab compacted samples (Group B)...............................................51 5.3 Interval plot for field cores (Group A)...................................................................54 5.4 Interval plot for field cores (Group B) ...................................................................54 5.5 Before vs. after sawing plot for CoreReaderTM Gmb ............................................69 5.6 Correlation of T166 Gmb and CoreReaderTM Gmb for SMA ...............................70 5.7 Correlation of T166 fast oven Gmb and CoreReaderTM Gmb for 100 mm and 150 mm field cores ...............................................................................................71 1 CHAPTER 1 INTRODUCTION PROBLEM STATEMENT The determination of the bulk specific gravity (Gmb) of bituminous paving mixture is an important part of the superpave mix design system and construction quality control/ quality assurance program. The bulk specific gravity is used to determine the air void content (VTM), voids in mineral aggregate (VMA), voids filled with asphalt (VFA) and percent density after compaction of bituminous mixtures. The Gmb of pavement cores are used in determining the percent compaction of hotmix asphalt (HMA) pavements. All of the above parameters are monitored closely during production to ensure satisfactory pavement performance. Problems or errors in measuring the Gmb can lead to pavement distresses such as rutting, stripping, bleeding, cracking, age hardening, and excessive permeability which finally have impact on pavement performance. With the introduction of coarser superpave mixtures and open graded specialty mixes, the ability of current procedures to accurately measure Gmb is being questioned. This is due to increased interconnected voids of coarse and open graded mixes, which can result in overapproximations of density and under approximation of VTM. Repeatability and consistency problem in Gmb test values are also more pronounced for coarse graded mixes. AASHTO T166 is used to determine the Gmb for samples with less than 2 two percent moisture absorption. AASHTO TP69, the CoreLokTM procedure, is recommended for samples with greater than two percent moisture absorption. Troxler® has developed the CoreReaderTM apparatus which can overcome all the drawbacks of AASHTO T166 and AASHTO TP69. The manufacturer claims that this device, when properly calibrated, provides repeatable and accurate measurements that are not operator dependent (1). The Troxler® 3660 CoreReaderTM uses gamma ray technology to determine the density and Gmb of HMA samples without using water displacement methods or dimensional analysis procedures. Initial results indicate that the CoreReaderTM has potential to accurately measure Gmb of HMA samples with interconnected voids (1). An evaluation of the CoreReaderTM could result in a more accurate measurement of Gmb, resulting in improved pavement performance. A second problem with AASHTO T166 is the time it takes to dry the sample and potential damage to the sample caused by drying at elevated temperatures. InstroTek® has developed the CoreDryTM apparatus that dries a core without heat, reducing testing time and allowing further testing of the sample without concern of damage to or artificial hardening of the sample due to heat of drying (2). The test procedure is listed in ASTM D7227. However, there was little published literature verifying that the dry mass determined from CoreDryTM is the same as determined using AASHTO T166. OBJECTIVES There were two main objectives of this study. The first objective was to determine if the Gmb of pavement cores determine using the CoreDryTM apparatus produces statistically similar results to AASHTO T166, resulting is substantial time savings to 3 contractors and for quality control and quality assurance works. The second objective was to determine if the CoreReaderTM produces statistically similar bulk specific gravities to AASHTO T166. If the results are different, correlations will be developed between the CoreReaderTM and AASHTO T166 Gmb. The effect of parallel surface and roughness of sample faces on CoreReaderTM Gmb will also be evaluated. SCOPE As the CoreDryTM and CoreReaerTM apparatus are new in determination of bulk specific gravity of HMA samples, there was little much literature available on the procedures to review. Only guidelines given by manufacturer and three unpublished articles were found and reviewed for this study. For the true comparison of AASHTO T166 Gmb with the Gmb obtained either by CoreDryTM or CoreReaerTM, a wide variety of samples ranging from dense to loose mix is needed. Different mixes with different void contents are necessary to evaluate the efficiency of the apparatus. The test results and analysis were done using lab compacted samples which were limited to ODOT S3, S4 and SMA mixes and field cores of diameter100 mm and 150 mm of unknown volumetric properties. 4 CHAPTER 2 REVIEW OF LITERATURE BULK SPECIFIC GRAVITY OF ASPHALT MIXES (Gmb) AASHTO defines the bulk specific gravity (Gmb) of an asphalt mix as the ratio of the weight in air of a unit volume of material (including both permeable and impermeable voids) at a stated temperature to the weight in air of an equal volume of gasfree distilled water at a stated temperature (3). The accurate measurement of bulk specific gravity (Gmb) of hotmix asphalt (HMA) is critical in mix design and determination of volumetric properties. The accurate determination of Gmb has been a topic of research for many DOTs and agencies for many years. The introduction of Superpave mix design methods in the late 1980’s resulted in the use of more coarse graded mixtures. With the use of coarse graded mixtures, agencies began noticing difficulty in accurately determining the Gmb of these coarse graded HMA mixes. There are several methods available for determination of Gmb of asphalt mixes. Common procedures are SSD method as outlined in AASHTO T166, Height–diameter or dimensional analysis method, CoreReaderTM (using Gamma rays), CoreLokTM (a vacuum sealing device) method as outlined in ASTM D6752 and AASHTO TP 69, and paraffin and Para film methods (AASHTO T275). 5 AASHTO T166 AASHTO T166 outlines the laboratory determination of bulk specific gravity by water displacement. The method consists of determination of dry weight and volume of the lab compacted as well as field core sample. AASHTO T166 uses the following formulas to calculate the bulk specific gravity and percent water absorption of asphalt mixture (1). Where, A= mass in grams of dry specimen in air B= mass in grams of the saturated surfacedry (SSD) specimen in air C= mass in grams of the specimen in water Method A For lab compacted samples, dry mass is the mass of the sample after cooling to room temperature at 25±5ºC (77±9ºF). The determination of the volume of the sample is by water displacement. In this method, the mass of sample immersed in water at 25±1ºC (77±1.8ºF) for 4±1 minute is the submerged mass (C) and the mass of specimen by blotting with a damp towel quickly is the surfacedry mass (B) (3). For filed core samples the dry mass (A) is defined as the mass at which further drying at 52±3ºC (125±5ºF) does not alter the mass by more than 0.05 %. Samples partially saturated with water are dried overnight at 52±3ºC (125±5ºF) and then weighed at twohour drying intervals until the mass loss is less than 0.05 %. Method B This method outlines the measurement of Gmb by volumeter. Method B consists of determining the dry mass (A) of lab compacted sample by cooling to 25±5ºC (77±9ºF) and saturateddry mass (B) by blotting a sample with a damp towel, immersed in water at 6 25±1ºC (77±1.8ºF) for 10 minutes. The mass of the volumeter filled with water at 25±1ºC (77±1.8ºF) (E) is taken and the following formula is used to calculate the Gmb (3). Where, D= mass in grams of the volumeter filled with water at 25±1ºC (77±1.8ºF) E= mass in grams of the volumeter filled with specimen and water at 25±1ºC (77±1.8ºF) A and B are as previously defined. If the percent water absorption is greater than 2 %, AASHTO T166 method B recommends using AASHTO T275 to determine the bulk specific gravity. Method C (Rapid Test) AASHTO T166 Method C outlines the procedure of determining the Gmb of lab compacted and field core samples which have a substantial amount of moisture and are not required for further testing. In this method, the determination of volume is similar to Method A. The only difference in this method is the dry mass (A). The sample is dried at 110±5ºC (230±9ºF) to a constant mass. Constant mass in this case is mass loss does not alter by more than 0.05 percent when weighed at 2hour intervals. The dry mass (A) is the mass of sample at room temperature when mass loss is less than 0.05 % (3). The only disadvantage of this method is it can damage the sample for further testing. ASTM D2726 ASTM D2726 outlines the procedure for determination of Gmb of asphalt mix (4). For the laboratory prepared sample, the dry mass (A), surfacedry mass (B) and submerged mass (C) are determined as in AASHTO T166. For the laboratory drilled and field drilled cores ASTM D2726 recommends drying the sample at 110±5ºC (230±9ºF) to a constant 7 mass. Constant mass in this case is mass loss does not alter by more than 0.1 percent when weighed at 2hour intervals. ASTM D2726 does not allow drying the drilled cores at reduced temperature such as 52ºC (4). COREDRYTM The best method to determine the dry state or constant mass of field or laboratory cut cores is still in question as there are a number of methods available and the accurate determination of the dry mass is necessary in calculating the bulk specific gravity of asphalt mixes. According to InstroTek ® (2), the CoreDryTM apparatus was introduced to overcome the problem. The CoreDryTM system uses high vacuum in conjunction with a thermoelectric cold trap to draw moisture out of a sample, evaporate the moisture, and subsequently condense the moisture in a separate chamber. It provides a constant mass in relatively less time than traditional ovendrying techniques. The vacuum system lowers the vapor pressure in the chamber holding the specimen to draw out and evaporate trapped moisture. As such, the specimen remains at or near room temperature, which helps to retain the HMA characteristics due to prolonged exposure to the heat and oxidation potential present in forceddraft ovens (5). The CoreDryTM is already accepted by ASTM and the test procedure is available as ASTM D7227. The apparatus consists of sample chamber, water trap system and key pad. The apparatus performs a self test when it is started. The operation of CoreDryTM is simple and easy. A sample is placed in the sample chamber and drying operation can be completed by hitting the start button. During the drying operation, the apparatus runs through a series of drying cycles at a reduced pressure until the dry condition is met. The 8 number of cycles depends on the amount of moisture present in sample. The cold trap system collects all the water drawn by vacuum action which needs to remove after each drying operation. Sucking of water from the sample by vacuum action and collecting trapped water in water chamber constitutes a cycle. The apparatus goes through a number of such cycles to remove the water present in sample (2). The CoreDryTM apparatus is shown in figure 2.1 FIGURE 2.1 InstroTek® CoreDryTM apparatus. 9 COREREADERTM The Troxler Model 3660 CoreReaderTM is a laboratory nuclear device used to measure the bulk specific gravity and density of laboratory and field specimens (4). The CoreReaderTM uses gamma rays for determination of the pavement density and bulk specific gravity. The gamma ray method of density measurement is based on the scattering and absorption properties of gamma rays with matter. When a gamma ray source of primary energy in the Compton range is placed near a material, and energy selective gamma ray detector is used for gamma ray counting, the scattered and unscattered gamma rays with energies in the Compton range can be counted exclusively and directly converted to the density or bulk specific gravity of the material (1). CoreReaderTM bulk specific measurement is a non destructive, operator independent test and does not harm the mix property for further testing. CoreReaderTM can be used for hot specimens, resulting in a time saving for cooling of laboratory compacted samples (6). The apparatus consists of sample chamber and key pad. A sample size of 100 mm or 150 mm fits into the sample chamber. The operator selects the sample size and inputs the height of specimen. The manufacturer recommends the input height should be the average height measured at six evenly spaced locations by a caliper having precision of ±0.1mm. The height of the sample should be 110120 mm for 150 mm diameter laboratory sample. Once this information has been entered and the START button pressed, the CoreReaderTM measures the specimen specific gravity (Gmb) and density and displays the results on the screen. If the operator enters a maximum specific gravity (Gmm), it also calculates and displays the air void content (VTM). CoreReaderTM 10 calculates Gmb using the entered height and diameter of the specimen. This requires that specimens need to be parallel with smooth edges for testing. The allowable angle between two faces is 3º. The apparatus needs calibration with the standard set of calibrating cylinders when moved to new place or used after long time (6). The CoreReaderTM apparatus is shown in figure 2.2. FIGURE 2.2 Troxler CoreReaderTM Model 3660. The nondestructive bulk specific gravity (Gmb) determination of laboratory prepared and cored pavement specimens allow for performance tests to be conducted on the same specimens used in the Gmb determinations. In addition to the time savings, more reliable correlation between densities and moduli of specimens may be achieved. Troxler claims the following measurement precision, 11 Repeatability (Single Laboratory) 0.006 Sp. Gravity 6 kg/m3 (0.3744 pcf) Reproducibility (Multi laboratory) 0.009 Sp. Gravity 9 kg/m3 (0.5616 pcf) Troxler also states that the researcher does not have to prepare as many sample replicates to measure both volumetric and mechanical properties (1). PREVIOUS RESEARCH As both products, the CoreDryTM and CoreReaderTM are only few years old, there has not been much research on the devices. There were few published articles on CoreDryTM and CoreReader TM found in the literature. Only three published articles, one on CoreReaderTM and two on CoreDryTM, were found. Although there is not much published data on CoreDryTM, it has been accepted for use and the procedure is found in ASTM D7227. CoreDryTM In 2006, Kevin D. Hall (5) performed a study to investigate the ability of the CoreDryTM vacuum drying system to provide consistent and accurate estimates of constant mass for compacted HMA specimens. The study focused on the efficacy of the drying systemprovision of constant mass condition for a range of initial saturation conditions, and the practicality of the drying system, regarding the time required for obtaining the constant mass determination. A total of 29 gyratory compacted specimens of three different aggregate sizes (NMAS) were used in the analysis. Two different sets, one with 2426 hours soaking at 25ºC (77ºF) and another with vacuum saturation were used in the evaluation. Further, 20 drilled cores of 100mm diameter and approximately 12 150 mm height were vacuum saturated and subsequently used for the analysis. Each set were fed in to the CoreDryTM for drying. Drying time and drying efficiency were evaluated based on the previously determined dry weight from AASHTO T166. The result of this study in second attempt of drying with CoreDryTM for 24 hour soaked samples, removed 0.002 to 0.032 percent of water which is well below the 0.05 percent threshold value used in ovendrying constant mass definition. For the vacuum saturated specimens, the dry mass obtained after CoreDryTM showed that the degree of drying was less than the 0.2 % of the original dry mass and the difference in dry mass ranged from 0.043 to 0.211 percent of dry mass. The increased percentage of difference in dry mass was higher for the higher saturation. CoreDryTM produces the same results, but with the increased drying time and number of attempts for the vacuum saturated specimens. This study concluded with the following remarks (5): i) The CoreDryTM vacuum drying system consistently provides a reasonable estimate of constant mass in its initial attempt. ii) The CoreDryTM vacuum drying system provides reasonable estimates of constant mass for specimens with degree of saturation ranging up to ‘fully saturated’. Neal Retzer (7) conducted a review of InstroTek®’s CoreDryTM apparatus in 2005. The research objective was to evaluate if the CoreDryTM compares well enough with the conventional oven dry method. Both 100 mm and 150 mm diameter field cut cores were used in the analysis. Cores were first tested in CoreDryTM and tested in rapid oven drying at 110±5ºC (AASHTO T166, Method C) for dry mass. This study reported that the average difference in density came out to be 0.17 % and never exceeded 0.6 %. 13 Similarly, the difference in bulk specific gravity difference averaged 0.004 and never exceeded 0.016. CoreDryTM removed 86.9 % of the water while oven drying removed 91.2 % after drying in CoreDryTM. This shows the rapid drying is more effective than CoreDryTM drying method. The results seem to be bias as oven drying is followed by CoreDryTM for all of the samples. To overcome the bias results, 12 more samples with 90 seconds vacuum saturation were tested. This time comparison of weight of the sample before saturation, after saturation, after drying with CoreDryTM and oven drying were made. The average efficiency of CoreDryTM in removing water from the vacuum saturated samples was found to be 86.9% where as the average efficiency was found to be 91.2 % for oven drying. Based on efficiency in removing the water from the samples, the final conclusion was made in favor of CoreDryTM apparatus and can be accepted as an alternative to oven drying method (7). CoreReaderTM In July 2006, Stacy G. Williams (7) evaluated the bulk specific gravity obtained from CoreReaderTM. The comparison was done among the specific gravities obtained by AASHTO T166, CoreLokTM, CoreReaderTM and HeightDiameter procedure. The study was carried out using two different aggregate sizes and three different levels of compaction to account the effect of aggregate size and compactive effort on Gmb. All together, 72 samples were used in this study. A two way ANOVA with Duncan’s ranking indicated the AASHTO T166 method being most repeatable and consistent where as CoreReaderTM was statistically different, and seemed to be more variable. Individually, minimum variability was found in AASHTO T166 method (coefficient of variance 0.317) where as maximum variability in case of CoreReaderTM method (coefficient of variance 14 2.200). The CoreReaderTM Gmb was found to be statistically different than the AASHTO T166 and other methods. The study has also indicated that the variability in measured Gmb using CoreReaderTM is more for mixes with larger aggregate size (NMAS 25.0 mm and 37.5 mm). In this study, some samples were with heights which were out of range required for CoreReaderTM Gmb testing and alternative proportional height calculation was utilized (8). In another independent study by the Highway Materials Lab at North Carolina State University, (9) data were collected on 108 different specimens. Among the data collected were repeated specific gravity measurements with the CoreReaderTM at different measurement intervals. The average standard deviation of all 108 specimens comparing 4minute and 8minute counts was 0.0018. The test results also indicated that the CoreReaderTM is more precise than other methods currently used because of the increased sensitivity to the volumetric differences. SUMMARY After the review of the available literature, CoreDryTM apparatus seems promising in drying the lab compacted as well as field core samples for Gmb determination. The Gmb determined using CoreReaderTM apparatus seems different than AASHTO T166. Gmb from CoreReaderTM apparatus is expected to be less repeatable than AASHTO T166. 15 CHAPTER 3 TEST PLAN MATERIALS Lab Samples Two types of samples were evaluated, lab compacted and field cores. For the lab compacted samples, three types of mixes were used, an ODOT S3 mix, an ODOT S4 mix and an ODOT stone matrix asphalt (SMA) mix . The S3 and S4 mixes were prepared in the OSU bituminous laboratory. The SMA samples were obtained from a contractor’s lab. For the lab compacted S3 and S4 mixes, two different sample heights, 95±5 mm and 115±5 mm were prepared. The 95±5 mm and 115±5 mm high specimens were compacted at 7±0.5% and 4±0.5% VTM. Table 3.1 shows the heights and VTMs of the S3 and S4 mixes prepared in the laboratory. Table 3.1. Test Specimens of S3 and S4 Mix Mix Sample Height (mm) Diameter (mm) VTM (%) 95±5 150 7±0.5 S3 115±5 150 4±0.5 95±5 150 7±0.5 S4 115±5 150 4±0.5 Determination of bulk specific gravity (Gmb) of lab compacted samples is important for different laboratory distress evaluation tests. Distresses are directly related to pavement 16 performance. Moisture Induced Damage Test (AASHTO T283), Hamburg Wheel Track Testing (AASHTO T324) etc are used to evaluate pavement performance. These tests need samples with specific volumetric properties, which are ultimately based on Gmb of test specimens. The laboratory compacted 95±5mm high, 7±0.5% VTM samples were used to simulate AASHTO T283 test specimens and the 115±5mm high, and 4±0.5% VTM samples were selected to simulate the AASHTO T324 test specimens. S3 and S4 Mixes ODOT S3 and S4 mixes are fine graded mixes with nominal maximum aggregate size (NMAS) of 19.0 mm (3/4 inches) and 12.5 mm (1/2 inches), respectively. The S3 and S4 mixture were made with PG 6422 asphalt. The gradation of aggregate used in preparation of test specimens and ODOT mix specifications are presented in table 3.2. The grain size distribution curve of aggregates used for S3 and S4 mixes are presented in figure 3.1. TABLE 3.2. S3 and S4 Mix Design % Passing ODOT Specification Sieve Size S3 S4 S3 S4 1" 100 100 100 3/4" 100 100 90100 100 1/2" 85 94 <90 90100 3/8" 69 89 <90 No.4 47 62 No.8 32 40 3149 3458 No.16 23 28 No.30 19 20 No.50 8 12 No.100 5 7 No.200 4 5.2 28 210 Pb (%) 4.1 4.95 4.1 min. 4.6 min 17 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Sieve Size (mm 0.45 ) % Passing . S3 S4 FIGURE 3.1 Grain size distribution curve of aggregate for S3 and S4 mixes. Stone Matrix Asphalt (SMA) Mix Stone Matrix Asphalt (SMA) is a special type of mix consisting of coarse aggregate with fines as mineral filler. It relies on stone onstone contact to provide strength. Generally, gapgraded aggregates are used to produce such a mix. The percentage of asphalt in an SMA mix is generally higher than a regular mix. The SMA specimens were obtained from a contractor’s lab, and the physical properties were not determined. A typical aggregate gradation for an SMA mix is shown in table 3.3 and typical grain size distribution curve in figure 3.2. 18 TABLE 3.3. Typical Gradation of Aggregate for SMA Sieve Size % passing 3/4" 100 1/2" 9097 3/8" 6085 No.4 2535 No.8 1525 No.200 812 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Sieve Size (mm 0.45 ) % Passing . SMA FIGURE 3.2 Typical grain size distribution curve for SMA mix. Field Cores Field cores of HMA were provided from various projects by a testing lab. There were two different sizes of cores provided, approximately 100 mm (4 inches) diameter and approximately 150mm (6 inches) diameter. All the cores upon arrival were numbered 19 with a sample marker and sorted into two sets. One set consisted of cores having both ends smooth and parallel and the other consisted of cores with one or both edges irregular. The set with both ends smooth were tested directly whereas the other set, with one or both the faces irregular, were first tested for CoreReaderTM Gmb using the average height and retested after being sawed to make the edges smooth and parallel. TEST PROCEDURES Lab Samples Two different sets of samples were prepared in the laboratory, one with 95±5 mm height of 7±0.5 % VTM to match the test specimens used for AASHTO T283 test and other set of specimens with 115±5 mm height of 4±0.5 % air void content to match the superpave mix design void requirements. Samples were compacted according to AASHTO T312. After compacting the samples, they were allowed to cool at room temperature overnight. After cooling to room temperature, the height of each sample was recorded at six evenly spaced locations using a digital caliper having precision of ±0.1mm. The average of six readings was reported as the height of the specimen. Samples were next tested in the CoreReaderTM apparatus using the measured height and reported as CoreReaderTM bulk specific gravity. After the CoreReaderTM Gmb measurement, the dry (initial dry), submerged and saturated surface dry (SSD) masses were obtained in accordance with AASHTO T166. The bulk specific gravity was calculated using the formula given below, The Gmb obtained using the initial dry mass is reported as T166 Gmb. The percent absorption of each sample was also calculated using the formula 20 If the percent absorption was above 2 %, the Gmb was determined using the CoreLokTM apparatus in accordance with AASHTO TP69 (ASTM D6752), and the bulk specific gravity obtained was reported as AASHTO T166 Gmb. For further testing, each set of 95mm and 115mm high samples of S3, S4 and SMA mixes were divided in to two groups, namely group A and B, and tested in two different sequences. Group A: After determining the SSD mass, samples were placed in an oven at 52±3ºC (125±5ºF) overnight. After oven drying overnight, the mass was measured at 2 hour intervals until the difference in mass was less than 0.05 %. This was reported as the slow oven dry mass of the sample. The bulk specific gravity calculated using equation 3.1 using the slow oven dry mass, and previously measured submerged and SSD mass in accordance with AASHTO T166, was reported as slow oven Gmb. When the slow oven drying was completed, the same sample was dried in the CoreDryTM apparatus (CoreDryTM mass). Finally, the sample was placed in an oven at 110±5ºC (230±9ºF) and the mass checked every 2 hours until the sample reached a constant mass, which is a mass loss of less than 0.05 % in a two hour period. The bulk specific gravity obtained at 110±5ºC is recorded as fast oven Gmb. Group B A second set of samples of equal number were tested in a similar method as group A. The only difference being the order of testing between the CoreDryTM and slow oven procedures. The initial dry, submerged and SSD masses were obtained and the Gmb 21 obtained based on initial dry mass is reported as T166 Gmb. After T166 Gmb, the same samples were dried in the CoreDryTM to get the CoreDryTM Gmb. Finally samples were processed for slow oven and then fast oven drying and reported as slow oven and fast oven Gmb. The sequence of testing for group A and group B lab samples is illustrated in the flow chart shown in figure 3.3. FIGURE 3.3 Test procedures for lab compacted sample. Field Cores The field cores had varying heights and diameters of either approximately 100 mm (4 inches) or approximately 150 mm (6 inches). The actual diameter for the small size cores ranged from 95.3 mm (3.75 inches) to 97.0 mm (3.82 inches) and the diameter Fast oven drying (Fast oven dry mass) Submerged mass Slow Oven drying (Slow oven dry mass) SSD mass Core drying (CoreDryTM mass) Lab sample CoreReaderTM Gmb measurement Height measurement Initial dry mass Core drying (CoreDryTM mass) Slow Oven drying (Slow oven dry mass) Group A Group B 22 of large size cores range from 143.6 mm (5.65 inches) to 154.0 mm (6.06 inches). The specified diameter of samples for the CoreReaderTM is either exactly 100 mm (4 inches) or exactly 150 mm (6 inches). Cores were assumed as 100 mm for all small size cores and 150 mm for all large size cores. Cores cannot be considered dry as lab compacted samples. Therefore, the cores were placed in the CoreDryTM apparatus prior to testing to reach the dry condition. After drying using the CoreDryTM, heights were measured and then testing followed. The CoreReaderTM testing, submerged mass, SSD mass, slow oven drying mass and fast oven drying mass were determined in the same group A and group B sequence as followed for laboratory prepared samples. Effect of Parallel Faces Before Sawing One of the objectives of this study was to determine the effect of end treatment on CoreReaderTM Gmb. For cores with one or both ends uneven, they were first dried in CoreDryTM and height was measured using a dial gauge at 12 different locations. The cores were then tested in CoreReaderTM using the average height obtained from dial gauge measurement. The Gmb so obtained is reported as CoreReaderTM Gmb before sawing. After Sawing The same cores tested above were then sawed to make the faces parallel and smooth. During the sawing care was taken to minimize the reduction in height. After sawing the cores, heights at six different locations were obtained with a digital caliper. The Gmb so obtained is reported is CoreReaderTM Gmb after sawing. These cores were 23 then placed in to regular testing described in phase II. The sequence of testing for group A and group B field cores is illustrated in the flow chart shown in figure 3.4. FIGURE 3.4 Test procedures for field core samples. Fast oven drying (Fast oven dry mass) Submerged mass Slow Oven drying (Slow oven dry mass) SSD mass Core drying (CoreDryTM mass) Field Cores Both ends smooth and Parallel? Height measurement Core drying (CoreDryTM mass) Yes Core drying (CoreDryTM mass) Slow Oven drying (Slow oven dry mass) CoreReaderTM Gmb measurement (before sawing) Sawing of cores No Method A Method B CoreReaderTM Gmb (after sawing) 24 ANALYSIS The main objectives of this study were to determine the drying efficiency of CoreDryTM and to evaluate the CoreReaderTM apparatus in determining the bulk specific gravity (Gmb) of asphalt paving mixtures. To meet the objectives, ANOVA with Duncan’s multiple range tests along with paired ttesting were used. Practical significance of any statistically different results was also taken into account while analyzing the test results. A correlation will be developed by regression analysis if the test results are found statistically as well as practically different. Phase I CoreDryTM In this phase the dry mass of field cores and lab compacted samples obtained using the CoreDryTM apparatus were compared with the dry mass obtained by slow oven and fast oven drying. For lab samples, one extra dry mass measurement was obtained, dry mass after cooling to room temperature, and was used in the analysis. Phase II CoreReaderTM This phase of the project concentrated on evaluation of Gmb obtained from the CoreReaderTM to that obtained from conventional water displacement method (AASHTO T166). The Gmb obtained after drying by CoreDryTM, slow oven and fast oven operation were used in this analysis phase. Phase III This phase of analysis consists of evaluation of effect of sample height and parallel faces on CoreReaderTM Gmb. This was accomplished by comparing the CoreReaderTM Gmb before sawing and CoreReaderTM Gmb after sawing. Paired ttest and ttest assuming equal variances were used in this analysis. 25 CHAPTER 4 TEST RESULTS The determination of bulk specific gravity of asphalt paving mixture was divided into two major parts, one using the CoreReaderTM apparatus and another using the AASHTO T166 procedure. Four different drying techniques were used in the AASHTO T166 procedure. The drying method used in AASHTO T166 includes: i) Drying the sample at room temperature for 24 hours (only applicable to lab compacted samples) ii) Drying using CoreDryTM apparatus iii) Drying at 52±3ºC (125±5ºF) for constant mass (Slow oven drying method) iv) Drying at 110±5ºC (230±9ºF) for constant mass (Fast oven or rapid drying method) Laboratory compacted ODOT S3, S4 and SMA mixes and field cores obtained from a contractor’s lab were used for testing. PHASE I COREDRYTM In this phase, lab compacted samples and field cores were tested for dry mass. For the lab compacted specimens, dry mass after cooling to room temperature (initial dry 26 mass), submerged and SSD mass and dry mass after slow oven and fast oven drying were obtained in accordance with AASHTO T166 and reported as initial dry mass, sub mass, SSD mass, slow oven dry mass and fast oven dry mass, respectively. In addition, dry mass of test specimens were obtained after drying in CoreDryTM and reported as CoreDryTM mass. In this phase, 59 laboratory compacted samples and 219 field cores were used. To prevent bias, the samples were divided into two sets for testing, group A and group B. Group A The lab compacted samples and field cores were tested for dry mass according to the following sequence of tests of group A samples: (i) CoreReaderTM Gmb, (ii) measurement of dry mass after cooling to room temperature (for lab compacted samples only), (iii) measurement of submerged mass, (iv) measurement of SSD mass, (v) measurement of dry mass after slow oven drying, (vi) measurement of dry mass after drying in CoreDryTM apparatus, and (vii) measurement of dry mass after fast oven drying. A total of 30 lab compacted samples and 103 field cores were tested. The test results for lab samples and field cores are presented in Table 4.1 and 4.2, respectively. Group B For this group, the lab compacted and field cores were tested for dry mass according to the following sequence: (i) CoreReaderTM Gmb, (ii) measurement of dry mass after cooling to room temperature (for lab compacted samples only), (iii) measurement of submerged mass, (iv) measurement of SSD mass, (v) measurement of dry mass after drying in CoreDryTM apparatus(vi) measurement of dry mass after slow oven drying, and (vii) measurement of dry mass after fast oven drying. A total of 29 lab 27 compacted samples and 116 field cores were tested. The test results for lab samples and field cores are presented in Tables 4.3 and 4.4, respectively. PHASE II COREREADERTM This phase of the project is the evaluation of Gmb obtained using the CoreReaderTM. The dry masses for lab compacted samples and field cores used in phase I were used in Gmb calculations for phase II. Therefore, the group A and B samples were the same as in phase I. All together, 59 laboratory compacted samples and 219 field cores were used in this phase, out of which 30 lab compacted samples and 103 field cores were tested in group A and 29 lab samples and 116 field cores were tested in group B. The results include the Gmb obtained after initial drying (T166 Gmb), slow oven drying (Slow oven Gmb), Fast oven drying (Fast oven Gmb), Gmb after drying in CoreDryTM (CoreDryTM Gmb) and Gmb obtained from CoreReaderTM apparatus (CoreReaderTM Gmb). The test results for lab samples and field cores for group A are presented in tables 4.5 and 4.6, respectively. Similarly, test results for group B lab samples and field cores are presented in tables 4.7 and 4.8, respectively. PHASE III This phase is the evaluation of the effect of height and parallel faces on CoreReaderTM Gmb. This section of test results consists of field cores only. The CoreReaderTM Gmb before sawing (CRD Gmb, before sawing) and CoreReaderTM Gmb after sawing (CRD Gmb, after sawing) were obtained according to test procedures for 28 field cores. A total of 94 field cores were tested. The test results are presented in table 4.9. TABLE 4.1. Lab Test Result of Lab Compacted Samples, Phase I, Group A Sample ID Mix Initial dry mass (g) Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) 95 (1) S3 3883.3 2283.3 3910.7 3886.7 3883.8 3883.2 95 (6) S3 3873.0 2272.5 3905.4 3874.1 3874.0 3874.0 95 (7) S3 3871.3 2275.9 3900.2 3871.3 3870.8 3870.8 95 (8) S3 3877.5 2277.2 3906.2 3879.1 3878.2 3877.8 115 (3) S3 4927.2 2943.5 4939.0 4927.5 4927.2 4923.6 115 (4) S3 4912.6 2936.1 4928.2 4914.6 4913.3 4910.4 115 (5) S3 4919.5 2934.9 4930.6 4920.6 4919.8 4916.5 115 (7) S3 4913.2 2935.1 4924.2 4913.7 4913.7 4913.7 115 (8) S3 4902.1 2928.7 4917.7 4902.6 4902.2 4902.2 95(2) S4 3591.3 2026.7 3615.0 3596.0 3593.2 3592.3 95(3) S4 3603.7 2033.8 3627.9 3609.0 3605.7 3604.9 95(4) S4 3595.6 2028.2 3620.0 3601.0 3597.7 3596.7 95(5) S4 3602.1 2033.1 3623.9 3605.9 3603.7 3603.0 115(1) S4 4515.0 2581.2 4520.9 4515.2 4515.1 4515.0 115(2) S4 4504.7 2578.1 4510.8 4504.8 4504.8 4504.7 115(3) S4 4502.1 2572.0 4508.9 4502.4 4502.3 4502.1 115(4) S4 4505.9 2577.4 4511.5 4506.1 4506.1 4506.0 S(1) SMA 4755.7 2771.1 4759.7 4755.9 4755.9 4755.7 S(2) SMA 4768.8 2719.3 4783.5 4770.1 4769.0 4768.6 S(3) SMA 4762.0 2744.9 4767.9 4762.3 4762.2 4762.0 S(4) SMA 4780.9 2730.8 4792.5 4781.5 4781.1 4780.8 S(5) SMA 4767.5 2755.5 4772.0 4767.8 4767.7 4767.6 S(6) SMA 4765.2 2713.3 4784.0 4767.2 4765.5 4765.0 S(7) SMA 4761.1 2717.7 4771.5 4762.3 4761.1 4760.8 S(8) SMA 4776.3 2717.1 4789.7 4777.9 4776.5 4776.2 S(9) SMA 4769.0 2770.5 4775.6 4769.4 4769.2 4769.0 S(10) SMA 4763.1 2738.7 4767.5 4763.4 4763.3 4763.1 S(11) SMA 4763.2 2736.2 4768.7 4763.3 4763.3 4763.2 S(12) SMA 4772.7 2721.0 4781.8 4773.5 4772.9 4772.7 S(13) SMA 4752.4 2766.7 4757.9 4752.6 4752.5 4752.3 29 TABLE 4.2. Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) A1 820.8 1493.2 1482.9 1482.9 1481.4 A2 745.7 1338.2 1330.9 1330.9 1329.8 A3 828.2 1512.6 1500.0 1500.0 1498.2 A4 617.0 1120.0 1108.1 1108.1 1107.1 A5 677.3 1228.9 1215.5 1215.5 1214.5 A6 682.1 1235.5 1226.3 1226.3 1224.1 A7 807.8 1448.2 1444.4 1444.4 1443.8 A8 747.3 1357.2 1346.5 1346.5 1345.2 A9 613.3 1120.9 1112.6 1112.6 1111.5 B1 265.8 478.7 476.5 476.4 476.1 B2 267.4 480.3 478.4 478.4 478.2 B3 384.7 701.9 691.7 691.1 689.7 B4 387.5 704.2 694.7 694.4 693.5 B5 441.9 800.2 796.6 796.5 796.2 B6 589.5 1078.8 1071.9 1071.5 1071.0 B7 662.5 1196.1 1192.2 1191.6 1191.1 B8 624.3 1133.7 1128.7 1128.7 1127.9 B9 642.0 1161.0 1156.5 1156.1 1155.3 B10 587.0 1075.7 1069.2 1068.4 1067.7 B11 683.0 1237.4 1231.9 1231.5 1230.9 T115 890.9 1551.7 1550.5 1550.5 1550.2 T116 969.3 1712.2 1709.3 1709.2 1708.4 T117 735.3 1286.1 1283.9 1283.8 1283.3 T118 833.7 1502.2 1480.6 1481.3 1480.3 T119 961.0 1688.9 1685.5 1685.4 1685.1 T120 2371.3 4085.1 4072.3 4071.1 4069.7 T121 646.7 1161.2 1148.8 1147.3 1145.8 T122 882.4 1552.1 1549.0 1549.0 1548.7 T123 713.5 1249.0 1247.4 1247.5 1247.2 T124 685.0 1204.4 1202.6 1202.6 1202.3 T125 1000.5 1779.6 1772.5 1772.2 1771.2 T126 662.3 1172.1 1172.1 1170.9 1169.9 T127 862.7 1535.9 1529.4 1529.3 1528.5 T21 731.8 1278.8 1277.2 1277.1 1277.1 T22 723.9 1281.6 1277.8 1277.7 1277.7 30 TABLE 4.2. (Con’t.) Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) T23 864.3 1531.2 1528.6 1528.4 1528.4 T24 795.0 1403.3 1399.7 1399.7 1399.6 T25 941.6 1672.7 1665.5 1664.7 1663.6 T26 783.4 1430.5 1404.9 1399.9 1393.6 T27 1000.8 1730.0 1728.8 1728.7 1728.7 T28 903.1 1581.6 1578.9 1578.8 1578.5 T29 896.7 1582.3 1578.1 1578.0 1577.8 T210 1454.3 2569.9 2563.5 2563.1 2562.1 T211 814.2 1435.5 1432.1 1432.1 1431.9 T212 798.8 1409.3 1405.6 1405.6 1405.4 T213 1033.4 1787.1 1785.5 1785.5 1785.5 T214 996.7 1739.6 1738.3 1738.3 1738.1 T215 1281.6 2235.8 2232.2 2232.2 2231.6 T216 788.4 1379.9 1378.3 1378.3 1378.2 T217 741.5 1310.8 1307.9 1307.9 1307.8 T218 861.8 1496.9 1495.7 1495.7 1495.6 T219 869.8 1550.5 1541.9 1541.9 1541.2 T220 1001.5 1745.9 1742.3 1742.3 1742.0 T221 717.4 1261.2 1259.2 1259.2 1259.2 T222 772.7 1374.7 1371.5 1371.5 1371.2 T223 892.4 1544.9 1544.0 1544.0 1543.9 T224 1354.6 2398.2 2386.2 2386.2 2385.3 SC1 1122.0 1957.7 1954.8 1954.8 1954.7 SC2 1311.5 2289.9 2286.6 2286.6 2286.5 SC3 1231.1 2177.5 2171.9 2171.5 2171.4 SC4 1129.7 1975.1 1971.1 1971.6 1971.5 SC5 1045.8 1839.7 1835.6 1835.5 1835.3 B32 932.3 1669.9 1664.7 1664.5 1663.9 B33 832.2 1504.6 1496.9 1496.4 1494.6 B34 857.7 1523.9 1520.8 1520.8 1520.5 B35 1180.2 2111.5 2105.3 2104.7 2104.1 B36 1006.1 1803.9 1798.0 1797.9 1797.4 B37 570.7 1040.5 1033.5 1032.7 1032.4 B38 879.9 1557.8 1554.4 1554.4 1554.1 B39 536.4 970.8 966.9 966.7 966.6 T136 981.8 1740.0 1734.1 1734.1 1733.6 31 TABLE 4.2. (Con’t.) Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) T137 1572.6 2721.0 2715.3 2714.4 2713.6 T138 1759.7 3034.8 3032.1 3032.1 3031.7 T139 1520.5 2616.0 2613.2 2613.1 2612.8 T140 2167.9 3787.2 3770.9 3765.7 3762.8 T141 2217.6 3815.5 3808.9 3808.1 3807.1 T142 1692.6 2903.8 2900.5 2900.5 2900.0 T143 1961.5 3373.5 3368.4 3368.0 3366.9 T144 1418.9 2459.0 2453.4 2453.3 2452.9 T271 1780.7 3070.9 3061.4 3061.2 3060.6 T272 1257.9 2227.4 2207.2 2207.1 2204.6 T273 970.4 1765.4 1751.6 1750.8 1749.0 T274 1799.6 3290.0 3264.1 3257.2 3256.9 T275 1512.4 2608.7 2604.5 2604.5 2604.0 T276 1479.3 2608.5 2604 2603.5 2603.1 T277 1756.2 3025.2 3019 3017.8 3015.0 T278 1441.1 2499.0 2491.8 2491.0 2490.2 T279 1416.6 2437.5 2435.2 2435.3 2435.1 T280 1469.7 2547.1 2532.9 2530.4 2529.2 T281 1483.7 2696.0 2674.1 2670.2 2666.9 T282 1333.7 2338.8 2330.7 2329.6 2328.6 T283 1060.9 1908.8 1900.9 1900.9 1899.3 T284 946.8 1632.9 1630.3 1630.3 1629.9 T285 2318.5 4129.3 4120.8 4120.7 4119.1 T286 2291.8 4021.0 4016.4 4016.2 4014.7 T287 1830.9 3152.8 3144.1 3142.9 3141.7 T288 967.3 1742.6 1739.8 1739.8 1739.6 T289 1149.6 1987.5 1983.7 1983.7 1983.2 T290 1284.9 2249.7 2247.4 2247.0 2246.5 T291 1114.8 1939.9 1933.8 1933.1 1932.4 T292 2311.5 4015.4 3999.6 3995.4 3994.1 T293 2126.0 3740.0 3732.8 3731.1 3728.7 32 TABLE 4.3. Lab Test Results of Lab Compacted Samples, Phase I, Group B Sample ID Mix Initial dry mass (g) Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) 95 (10) S3 3857.3 2262.1 3888.3 3858.3 3857.4 3857.2 95(11) S3 3887.2 2280.0 3914.6 3887.8 3887.3 3887.3 95(12) S3 3862.8 2261.1 3893.0 3863.1 3862.9 3862.8 95(13) S3 3879.0 2279.0 3907.2 3879.8 3878.1 3878.1 115(9) S3 4928.6 2942.5 4938.7 4928.7 4928.6 4928.5 115(10) S3 4907.3 2935.6 4919.1 4907.8 4907.3 4907.2 115 (11) S3 4921.8 2941.7 4930.8 4922.2 4921.8 4921.5 115(12) S3 4912.9 2926.7 4920.1 4913.1 4913.0 4913 115(13) S3 4921.6 2940.4 4931.4 4921.7 4921.6 4921.6 95(6) S4 3596.7 2029.5 3618.5 3597.2 3596.8 3596.7 95(8) S4 3607.4 2036.9 3627.9 3608.1 3607.5 3607.4 95(9) S4 3594.2 2029.3 3620.6 3594.9 3594.2 3594.1 95(10) S4 3605.1 2036.1 3626.4 3606.0 3605.2 3605.1 115(5) S4 4505.3 2583.4 4513.9 4505.7 4505.5 4505.3 115(6) S4 4521.4 2591.3 4529.0 4521.4 4521.4 4521.4 115(7) S4 4510.1 2581.9 4519.2 4510.2 4510.2 4510.1 115(8) S4 4518.3 2587.3 4524.6 4518.3 4518.3 4518.3 S(14) SMA 4768.8 2714.9 4786.9 4769.2 4768.5 4768.2 S(15) SMA 4764.9 2780.0 4769.2 4764.9 4764.7 4764.5 S(16) SMA 4774.1 2749.0 4784.4 4774.3 4773.9 4773.6 S(17) SMA 4762.7 2778.3 4767.3 4762.7 4762.5 4762.2 S(18) SMA 4772.0 2739.9 4780.6 4772.2 4771.8 4771.6 S(19) SMA 4773.7 2778.6 4779.8 4773.7 4773.3 4773.1 S(20) SMA 4765.0 2774.2 4769.0 4765.1 4764.8 4764.5 S(21) SMA 4766.1 2773.7 4771.8 4766.1 4765.8 4765.5 S(22) SMA 4773.0 2776.6 4779.9 4773 4772.7 4772.4 S(23) SMA 4765.4 2744.9 4770.8 4765.4 4765.2 4764.9 S(24) SMA 4777.3 2749.7 4787.1 4777.4 4777.0 4776.6 S(25) SMA 4766.7 2772.3 4772.6 4766.7 4766.4 4766.2 33 TABLE 4.4. Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) A10 689.4 1240.5 1234.3 1233.6 1232.9 A11 730.6 1326.7 1316.7 1316.0 1315.4 B12 1006.0 1791.2 1791.2 1790.3 1789.9 B13 1003.3 1788.8 1788.8 1787.7 1787.4 B14 444.5 802.8 802.8 802.2 802.0 B15 385.7 698.2 698.2 697.5 696.9 B16 636.4 1149.8 1145.1 1144.4 1143.7 B17 571.8 1021.0 1021.0 1020.4 1020.1 B18 714.8 1287.3 1287.3 1286.6 1286.4 B19 625.9 1136.2 1136.2 1135.6 1135.4 B20 684.4 1247.8 1247.8 1246.9 1246.6 B21 633.8 1137.9 1137.9 1137.2 1136.8 B22 570.4 1049.1 1049.1 1048.4 1048.2 T11 687.9 1207.0 1204.6 1204.0 1203.7 T12 925.9 1638.9 1632.3 1631.8 1631.4 T13 929.2 1632.0 1629.3 1628.7 1628.3 T14 835.0 1501.9 1486.6 1485.4 1484.7 T15 919.6 1602.4 1601.3 1600.9 1600.8 T16 804.8 1422.0 1418.9 1417.7 1417.4 T17 775.2 1377.9 1373.3 1372.6 1372.0 T18 879.0 1555.0 1552.6 1552.1 1551.8 T19 807.4 1406.1 1404.9 1404.7 1704.6 T110 2059.1 3533.6 3528.9 3527.6 3527.3 T111 1775.2 3060.9 3052.7 3051.8 3051.7 T112 1805.2 3128.8 3123.1 3122.4 3122.1 T113 846.5 1489.0 1487.5 1487.3 1487.0 T114 910.9 1587.3 1586.3 1586.1 1585.9 T225 772.2 1351.9 1350.7 1350.3 1350.2 T226 846.2 1497.2 1494.4 1493.9 1493.8 T227 909.4 1573.3 1571.8 1571.4 1571.3 T228 772.1 1353.6 1351.6 1351.2 1351.0 T229 792.4 1386.7 1384.7 1384.4 1384.2 T230 741.7 1316.2 1310.0 1308.8 1308.5 T231 799.1 1409.4 1406.9 1406.4 1406.2 T232 833.7 1449.9 1448.1 1447.8 1447.6 T233 902.2 1588.1 1585.3 1584.7 1584.4 34 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) T234 979.7 1715.2 1713.0 1712.4 1712.1 T235 853.4 1497.8 1495.8 1495.2 1495.1 T236 824.1 1464.8 1456.7 1455.2 1454.8 T237 897.0 1565.8 1562.6 1562.0 1561.7 T238 896.9 1584.5 1579.6 1578.9 1578.5 T239 864.5 1513.6 1511.1 1510.6 1510.4 T240 985.3 1728.8 1727.2 1726.9 1726.9 T241 889.7 1563.3 1561.3 1560.9 1560.8 T242 890.8 1554.1 1552.4 1552.1 1552.0 T243 929.3 1618.5 1617.2 1617.0 1617.0 T244 991.9 1753.9 1750.0 1749.3 1749.1 T245 935.1 1625.0 1623.4 1623.1 1623.0 T246 893.9 1553.4 1552.0 1551.7 1551.7 T247 779.5 1368.8 1367.0 1366.8 1366.7 T286 1508.1 2640.3 2634.5 2633.7 2633.5 T213B 929.0 1622.0 1620.1 1619.9 1619.9 SC6 1254.2 2196.1 2193.2 2192.9 2192.7 SC7 1375.8 2392.3 2388.9 2388.8 2388.7 SC8 1280.4 2263.9 2257.5 2257.1 2256.9 SC9 1294.9 2260.4 2256.5 2256.2 2256.1 H1 946.0 1724.0 1713.9 1712.8 1712.3 H2 720.3 1270.3 1269.0 1268.8 1268.7 H3 1764.0 3091.8 3085.5 3084.6 3084.3 H4 690.6 1208.4 1206.8 1206.6 1206.3 H5 1496.2 2606.2 2603.0 2602.2 2601.7 H6 1255.4 2231.0 2223.1 2221.8 2221.2 H7 1112.2 1915.4 1913.5 1913.1 1912.8 H8 1420.8 2454.6 2453.1 2452.8 2452.3 H9 1052.5 1808.9 1807.2 1806.9 1806.4 H10 899.9 1606.0 1603.2 1602.5 1601.9 H11 1223.8 2180.4 2168.2 2166.7 2166.0 H12 923.7 1611.0 1607.4 1606.7 1605.5 H13 1697.7 2962.8 2959.5 2958.8 2958.2 A12 781.8 1420.1 1409.1 1407.8 1407.3 A13 587.9 1055.2 1049.7 1048.8 1048.5 35 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) A14 777.2 1416.3 1406.2 1404.6 1403.7 A15 637.9 1149.1 1141.3 1140.1 1139.4 A16 690.5 1246.7 1241.5 1240.3 1239.9 A17 554.6 1002.6 999.0 998.2 997.6 A18 556.3 1008.8 1000.8 999.7 999.2 B23 619.5 1121.1 1117.9 1117.0 1116.7 B24 621.2 1121.5 1118.9 1117.8 1117.7 B25 629.1 1153.1 1146.3 1145.0 1144.8 B26 331.9 602.0 599.4 598.8 598.6 B27 828.0 1503.1 1492.6 1490.7 1490.2 B28 953.0 1705.4 1701.4 1700.1 1699.7 B29 815.0 1446.6 1444.3 1443.4 1443.2 B30 1050.5 1882.9 1877.9 1876.4 1876.0 B31 527.3 954.3 949.7 948.3 947.8 T128 839.7 1491.3 1489.2 1488.4 1488.0 T129 1021.8 1768.1 1757.3 1754.1 1752.6 T130 1948.0 3369.9 3367.0 3360.0 3365.9 T131 1439.2 2481.2 2476.9 2475.7 2474.9 T132 1535.4 2671.2 2668.5 2667.5 2667.3 T133 923.2 1583.3 1581.9 1581.2 1580.7 T134 1418.3 2430.8 2428.1 2428.1 2427.1 T135 1803.2 3104.9 3102.6 3102.6 3101.2 T248 991.0 1831.0 1806.7 1799.5 1797.5 T249 761.5 1332.7 1330.6 1329.8 1329.5 T250 1751.8 3053.2 3046.0 3044.2 3043.5 T251 1647.4 2854.0 2844.7 2841.9 2841.2 T252 1683.2 2908.3 2904.3 2903.0 2902.4 T253 1436.9 2521.3 2515.7 2514.6 2514.0 T254 3192.9 5571.1 5532.0 5527.3 5525.0 T255A 916.3 1634.5 1631.7 1630.6 1630.2 T255B 1840.0 3168.7 3160.6 3157.3 3154.4 T256 1717.5 2982.7 2970.7 2969.1 2968.5 T257 2300.6 3987.3 3966.0 3962.0 3958.7 T258 1015.6 1873.1 1832.6 1827.3 1824.6 T259 3235.3 5595.3 5588.5 5586.2 5584.9 36 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) T260 2060.8 3554.6 3544.5 3542.1 3541.4 T261 977.1 1773.2 1765.7 1763.1 1761.6 T262 1570.4 2722.0 2718.9 2717.9 2717.6 T263 1145.8 1986.8 1983.2 1982.3 1982.1 T264 1666.4 2874.4 2870.5 2869.9 2869.8 T265 1543.9 2679.0 2671.7 2670.6 2670.4 T266 1415.7 2487.0 2442.4 2439.1 2438.2 T267 1699.1 2934.3 2929.3 2928.2 2928.1 T268 1070.4 1850.9 1846.1 1845.2 1845.0 T269 848.4 1531.3 1523.3 1519.5 1517.5 37 TABLE 4.5. Lab Test Results of Lab Compacted Samples, Phase II, Group A Sample ID Mix CoreReaderTM Gmb T166 Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb 95 (1) S3 2.339 2.386 2.388 2.387 2.386 95(6) S3 2.332 2.372 2.373 2.372 2.373 95(7) S3 2.324 2.383 2.383 2.383 2.383 95(8) S3 2.337 2.380 2.381 2.381 2.380 115(3) S3 2.437 2.469 2.469 2.469 2.467 115(4) S3 2.447 2.466 2.467 2.466 2.465 115(5) S3 2.460 2.465 2.466 2.465 2.464 115(7) S3 2.449 2.470 2.470 2.470 2.470 115(8) S3 2.447 2.465 2.465 2.465 2.465 95(2) S4 2.224 2.261 2.262 2.262 2.262 95(3) S4 2.227 2.261 2.262 2.262 2.261 95(4) S4 2.229 2.259 2.260 2.260 2.260 95(5) S4 2.222 2.264 2.265 2.265 2.265 115(1) S4 2.309 2.328 2.328 2.328 2.328 115(2) S4 2.305 2.331 2.331 2.331 2.331 115(3) S4 2.315 2.324 2.325 2.324 2.324 115(4) S4 2.319 2.330 2.330 2.330 2.330 S(1) SMA 2.367 2.391 2.392 2.392 2.391 S(2) SMA 2.279 2.310 2.311 2.310 2.310 S(3) SMA 2.295 2.354 2.354 2.354 2.354 S(4) SMA 2.278 2.319 2.319 2.319 2.319 S(5) SMA 2.313 2.364 2.364 2.364 2.364 S(6) SMA 2.247 2.301 2.302 2.301 2.301 S(7) SMA 2.275 2.318 2.319 2.318 2.318 S(8) SMA 2.253 2.304 2.305 2.305 2.304 S(9) SMA 2.351 2.378 2.379 2.379 2.378 S(10) SMA 2.301 2.348 2.348 2.348 2.348 S(11) SMA 2.281 2.344 2.344 2.344 2.344 S(12) SMA 2.265 2.316 2.316 2.316 2.316 S(13) SMA 2.358 2.387 2.387 2.387 2.387 38 TABLE 4.6. Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb A1 100 2.173 2.205 2.205 2.203 A2 100 2.214 2.246 2.246 2.244 A3 100 2.143 2.192 2.192 2.189 A4 100 2.154 2.203 2.203 2.201 A5 100 2.140 2.204 2.204 2.202 A6 100 2.187 2.216 2.216 2.212 A7 100 2.229 2.255 2.255 2.255 A8 100 2.167 2.208 2.208 2.206 A9 100 2.126 2.192 2.192 2.190 B1 100 2.194 2.238 2.238 2.236 B2 100 2.216 2.247 2.247 2.246 B3 100 2.118 2.181 2.179 2.174 B4 100 2.135 2.194 2.193 2.190 B5 100 2.166 2.223 2.223 2.222 B6 100 2.146 2.191 2.190 2.189 B7 100 2.191 2.234 2.233 2.232 B8 100 2.157 2.216 2.216 2.214 B9 100 2.204 2.228 2.228 2.226 B10 100 2.156 2.188 2.186 2.185 B11 100 2.190 2.222 2.221 2.220 T115 150 2.276 2.346 2.346 2.346 T116 150 2.228 2.301 2.301 2.300 T117 150 2.299 2.331 2.331 2.330 T118 150 2.144 2.215 2.216 2.214 T119 150 2.236 2.316 2.315 2.315 T120 150 2.339 2.376 2.375 2.375 T121 150 2.172 2.233 2.230 2.227 T122 150 2.246 2.313 2.313 2.313 T123 150 2.268 2.329 2.330 2.329 T124 150 2.253 2.315 2.315 2.315 T125 150 2.205 2.275 2.275 2.273 T126 150 2.179 2.299 2.297 2.295 T127 150 2.190 2.272 2.272 2.270 T21 150 2.307 2.335 2.335 2.335 T22 150 2.209 2.291 2.291 2.291 39 TABLE 4.6. (Con’t.) Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb T23 150 2.231 2.292 2.292 2.292 T24 150 2.237 2.301 2.301 2.301 T25 150 2.199 2.278 2.277 2.275 T26 150 2.076 2.171 2.163 2.154 T27 150 2.322 2.371 2.371 2.371 T28 150 2.265 2.327 2.327 2.326 T29 150 2.246 2.302 2.302 2.301 T210 150 2.223 2.298 2.298 2.297 T211 150 2.254 2.305 2.305 2.305 T212 150 2.226 2.302 2.302 2.302 T213 150 2.331 2.369 2.369 2.369 T214 150 2.284 2.340 2.340 2.340 T215 150 2.262 2.339 2.339 2.339 T216 150 2.264 2.330 2.330 2.330 T217 150 2.217 2.297 2.297 2.297 T218 150 2.300 2.355 2.355 2.355 T219 150 2.192 2.265 2.265 2.264 T220 150 2.262 2.341 2.341 2.340 T221 150 2.261 2.316 2.316 2.316 T222 150 2.217 2.278 2.278 2.278 T223 150 2.316 2.366 2.366 2.366 T224 150 2.220 2.287 2.287 2.286 SC1 150 2.251 2.339 2.339 2.339 SC2 150 2.263 2.337 2.337 2.337 SC3 150 2.197 2.295 2.294 2.294 SC4 150 2.230 2.332 2.332 2.332 SC5 150 2.203 2.312 2.312 2.312 B32 100 2.246 2.257 2.257 2.256 B33 100 2.204 2.226 2.225 2.223 B34 100 2.257 2.283 2.283 2.282 B35 100 2.245 2.261 2.260 2.259 B36 100 2.235 2.254 2.254 2.253 B37 100 2.177 2.200 2.198 2.198 B38 100 2.260 2.293 2.293 2.293 B39 100 2.202 2.226 2.225 2.225 40 TABLE 4.6. (Con’t.) Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb B40 100 2.235 2.261 2.260 2.260 T136 150 2.236 2.287 2.287 2.286 T137 150 2.312 2.364 2.364 2.363 T138 150 2.332 2.378 2.378 2.378 T139 150 2.343 2.385 2.385 2.385 T140 150 2.267 2.329 2.326 2.324 T141 150 2.352 2.384 2.383 2.383 T142 150 2.364 2.395 2.395 2.394 T143 150 2.352 2.386 2.385 2.384 T144 150 2.313 2.359 2.359 2.358 T271 150 2.343 2.373 2.373 2.372 T272 150 2.204 2.277 2.277 2.274 T273 150 2.160 2.203 2.202 2.200 T274 150 2.163 2.190 2.185 0.000 T275 150 2.340 2.376 2.376 2.375 T276 150 2.261 2.306 2.306 2.305 T277 150 2.359 2.379 2.378 2.376 T278 150 2.310 2.355 2.355 2.354 T279 150 2.348 2.385 2.385 2.385 T280 150 2.321 2.351 2.349 2.348 T281 150 2.152 2.206 2.203 2.200 T282 150 2.254 2.319 2.318 2.317 T283 150 2.228 2.242 2.242 2.240 T284 150 2.311 2.376 2.376 2.376 T285 150 2.253 2.276 2.276 2.275 T286 150 2.316 2.323 2.323 2.322 T287 150 2.348 2.378 2.378 2.377 T288 150 2.216 2.244 2.244 2.244 T289 150 2.341 2.367 2.367 2.367 T290 150 2.301 2.329 2.329 2.328 T291 150 2.290 2.344 2.343 2.342 T292 150 2.317 2.347 2.345 2.344 T293 150 2.300 2.313 2.312 2.310 41 TABLE 4.7. Lab Test Results of Lab Compacted Samples, Phase II, Group B Sample ID Mix CoreReaderTM Gmb T166 Gmb CoreDryTM Gmb Slow oven Gmb Fast oven Gmb 95(10) S3 2.312 2.372 2.373 2.372 2.372 95(11) S3 2.332 2.378 2.378 2.378 2.378 95(12) S3 2.311 2.367 2.367 2.367 2.367 95(13) S3 2.326 2.382 2.383 2.382 2.382 115 (9) S3 2.469 2.469 2.469 2.469 2.469 115(10) S3 2.439 2.474 2.474 2.474 2.474 115(11) S3 2.437 2.474 2.475 2.474 2.474 115(12) S3 2.458 2.465 2.465 2.465 2.465 115(13) S3 2.458 2.472 2.472 2.472 2.472 95(6) S4 2.231 2.263 2.264 2.264 2.263 95(8) S4 2.232 2.267 2.268 2.267 2.267 95(9) S4 2.217 2.259 2.259 2.259 2.259 95(10) S4 2.251 2.267 2.267 2.267 2.267 115(5) S4 2.303 2.334 2.334 2.334 2.334 115(6) S4 2.316 2.333 2.333 2.333 2.333 115(7) S4 2.314 2.328 2.328 2.328 2.328 115(8) S4 2.314 2.332 2.332 2.332 2.332 S(14) SMA 2.260 2.302 2.302 2.301 2.301 S(15) SMA 2.376 2.395 2.395 2.395 2.395 S(16) SMA 2.294 2.346 2.346 2.345 2.345 S(17) SMA 2.371 2.395 2.395 2.394 2.394 S(18) SMA 2.296 2.338 2.339 2.338 2.338 S(19) SMA 2.371 2.385 2.385 2.385 2.385 S(20) SMA 2.367 2.389 2.389 2.389 2.388 S(21) SMA 2.338 2.385 2.385 2.385 2.385 S(22) SMA 2.363 2.383 2.383 2.382 2.382 S(23) SMA 2.318 2.352 2.352 2.352 2.352 S(24) SMA 2.310 2.345 2.345 2.345 2.344 S(25) SMA 2.346 2.383 2.383 2.383 2.383 42 TABLE 4.8. Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb A10 100 2.191 2.240 2.238 2.237 A11 100 2.185 2.209 2.208 2.207 B12 100 2.261 2.281 2.280 2.280 B13 100 2.242 2.277 2.276 2.275 B14 100 2.186 2.241 2.239 2.238 B15 100 2.117 2.234 2.232 2.230 B16 100 2.182 2.230 2.229 2.228 B17 100 2.225 2.273 2.272 2.271 B18 100 2.193 2.249 2.247 2.247 B19 100 2.138 2.227 2.225 2.225 B20 100 2.148 2.215 2.213 2.213 B21 100 2.178 2.257 2.256 2.255 B22 100 2.066 2.192 2.190 2.190 T11 150 2.282 2.321 2.319 2.319 T12 150 2.213 2.289 2.289 2.288 T13 150 2.255 2.318 2.317 2.317 T14 150 2.154 2.229 2.227 2.226 T15 150 2.275 2.345 2.345 2.344 T16 150 2.225 2.299 2.297 2.297 T17 150 2.222 2.279 2.277 2.276 T18 150 2.260 2.297 2.296 2.296 T19 150 2.274 2.347 2.346 2.847 T110 150 2.358 2.393 2.392 2.392 T111 150 2.254 2.374 2.374 2.374 T112 150 2.305 2.360 2.359 2.359 T113 150 2.257 2.315 2.315 2.314 T114 150 2.279 2.345 2.345 2.345 T225 150 2.289 2.330 2.329 2.329 T226 150 2.222 2.296 2.295 2.295 T227 150 2.313 2.368 2.367 2.367 T228 150 2.278 2.324 2.324 2.323 T229 150 2.290 2.330 2.329 2.329 T230 150 2.189 2.280 2.278 2.278 T231 150 2.264 2.305 2.304 2.304 T232 150 2.285 2.350 2.350 2.349 T233 150 2.270 2.311 2.310 2.310 43 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb T234 150 2.286 2.329 2.328 2.328 T235 150 2.248 2.321 2.320 2.320 T236 150 2.214 2.274 2.271 2.271 T237 150 2.286 2.336 2.336 2.335 T238 150 2.228 2.297 2.296 2.296 T239 150 2.283 2.328 2.327 2.327 T240 150 2.272 2.323 2.323 2.323 T241 150 2.246 2.318 2.317 2.317 T242 150 2.295 2.340 2.340 2.340 T243 150 2.292 2.346 2.346 2.346 T244 150 2.223 2.297 2.296 2.295 T245 150 2.302 2.353 2.353 2.353 T246 150 2.303 2.353 2.353 2.353 T247 150 2.284 2.320 2.319 2.319 T286 150 2.265 2.327 2.326 2.326 T213B 150 2.290 2.338 2.338 2.338 SC6 150 2.249 2.328 2.328 2.328 SC7 150 2.270 2.350 2.350 2.350 SC8 150 2.196 2.295 2.295 2.295 SC9 150 2.244 2.337 2.337 2.337 H1 150 2.181 2.203 2.201 2.201 H2 150 2.276 2.307 2.307 2.307 H3 150 2.283 2.324 2.323 2.323 H4 150 2.339 2.331 2.330 2.330 H5 150 2.308 2.345 2.344 2.344 H6 150 2.26 2.279 2.277 2.277 H7 150 2.354 2.382 2.381 2.381 H8 150 2.353 2.373 2.372 2.372 H9 150 2.373 2.389 2.388 2.388 H10 150 2.244 2.270 2.270 2.269 H11 150 2.234 2.267 2.265 2.264 H12 150 2.320 2.339 2.338 2.336 H13 150 2.311 2.339 2.339 2.338 A12 100 2.195 2.195 2.206 2.205 A13 100 2.236 2.236 2.244 2.244 44 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb A14 100 2.183 2.183 2.198 2.196 A15 100 2.200 2.200 2.230 2.229 A16 100 2.208 2.208 2.230 2.229 A17 100 2.209 2.209 2.228 2.227 A18 100 2.171 2.171 2.209 2.208 B23 100 2.210 2.210 2.227 2.226 B24 100 2.218 2.218 2.234 2.234 B25 100 2.147 2.147 2.185 2.185 B26 100 2.178 2.178 2.217 2.216 B27 100 2.186 2.186 2.208 2.207 B28 100 2.232 2.232 2.260 2.259 B29 100 2.257 2.257 2.285 2.285 B30 100 2.244 2.244 2.254 2.254 B31 100 2.192 2.192 2.221 2.220 T128 150 2.250 2.285 2.284 2.284 T129 150 2.259 2.355 2.350 2.348 T130 150 2.338 2.368 2.363 2.367 T131 150 2.337 2.377 2.376 2.375 T132 150 2.313 2.349 2.349 2.348 T133 150 2.365 2.396 2.395 2.395 T134 150 2.342 2.398 2.398 2.397 T135 150 2.355 2.383 2.383 2.382 T248 150 2.107 2.151 2.142 2.140 T249 150 2.322 2.329 2.328 2.328 T250 150 2.303 2.341 2.339 2.339 T251 150 2.329 2.358 2.355 2.355 T252 150 2.314 2.371 2.370 2.369 T253 150 2.274 2.320 2.319 2.318 T254 150 2.330 2.326 2.324 2.323 T255A 150 2.246 2.272 2.270 2.270 T255B 150 2.355 2.379 2.376 2.374 T256 150 2.317 2.348 2.347 2.346 T257 150 2.353 2.351 2.349 2.347 T258 150 2.088 2.137 2.131 2.128 T259 150 2.365 2.368 2.367 2.366 45 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb T260 150 2.349 2.373 2.371 2.371 T261 150 2.175 2.218 2.215 2.213 T262 150 2.315 2.361 2.360 2.360 T263 150 2.310 2.358 2.357 2.357 T264 150 2.333 2.376 2.376 2.376 T265 150 2.317 2.354 2.353 2.353 T266 150 2.218 2.280 2.277 2.276 T267 150 2.328 2.372 2.371 2.371 T268 150 2.310 2.365 2.364 2.364 T269 150 2.211 2.231 2.225 2.222 TABLE 4.9. CoreReaderTM Gmb Before and After Sawing of Field Cores, Phase III Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) B32 100 2.243 2.246 A12 100 2.151 2.195 B33 100 2.195 2.204 A13 100 2.217 2.236 B34 100 2.243 2.257 A14 100 2.184 2.183 B35 100 2.255 2.245 A15 100 2.188 2.200 B36 100 2.230 2.235 A16 100 2.189 2.208 B37 100 2.162 2.177 A17 100 2.161 2.209 B38 100 2.275 2.260 A18 100 2.157 2.171 B39 100 2.179 2.202 B23 100 2.199 2.210 B40 100 2.245 2.235 B24 100 2.192 2.218 T136 150 2.154 2.236 B25 100 2.142 2.147 T137 150 2.236 2.312 B26 100 2.168 2.178 T138 150 2.33 2.332 B27 100 2.183 2.186 T139 150 2.364 2.343 B28 100 2.257 2.232 T140 150 2.268 2.267 B29 100 2.245 2.257 T141 150 2.354 2.352 B30 100 2.234 2.244 T142 150 2.511 2.364 B31 100 2.180 2.192 T143 150 2.373 2.352 T128 150 2.220 2.250 46 TABLE 4.9.(Con’t.) CoreReaderTM Gmb Before and After Sawing of Field Cores, Phase III Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) T144 150 2.367 2.313 T129 150 2.148 2.259 T271 150 2.321 2.343 T130 150 2.335 2.338 T272 150 2.185 2.204 T131 150 2.318 2.337 T273 150 2.137 2.160 T132 150 2.298 2.313 T274 150 2.128 2.163 T133 150 2.387 2.365 T275 150 2.318 2.340 T134 150 2.550 2.342 T276 150 2.241 2.261 T135 150 2.396 2.355 T277 150 2.483 2.359 T248 150 2.070 2.107 T278 150 2.300 2.310 T249 150 2.180 2.322 T279 150 2.313 2.348 T250 150 2.303 2.303 T280 150 2.280 2.321 T251 150 2.339 2.329 T281 150 2.146 2.152 T252 150 2.284 2.314 T282 150 2.206 2.254 T253 150 2.258 2.274 T283 150 2.154 2.228 T254 150 2.300 2.330 T284 150 2.376 2.311 T255A 150 2.209 2.246 T285 150 2.254 2.253 T255B 150 2.308 2.355 T286 150 2.265 2.316 T256 150 2.271 2.317 H1 150 2.070 2.181 T257 150 2.338 2.353 H2 150 2.170 2.276 T258 150 2.049 2.088 H3 150 2.259 2.283 T259 150 2.337 2.365 H4 150 2.178 2.339 T260 150 2.315 2.349 H5 150 2.302 2.308 T261 150 2.139 2.175 H6 150 2.234 2.26 T262 150 2.280 2.315 H7 150 2.262 2.354 T263 150 2.491 2.310 H8 150 2.337 2.353 T264 150 2.312 2.333 H9 150 2.318 2.373 T265 150 2.275 2.317 H10 150 2.253 2.244 T266 150 2.194 2.218 H11 150 2.195 2.234 T267 150 2.312 2.328 H12 150 2.282 2.320 T268 150 2.318 2.310 H13 150 2.287 2.311 T269 150 1.558 2.211 47 CHAPTER 5 ANALYSIS OF TEST RESULTS This chapter provides the analysis of the experimental test data. Two different statistical analyses techniques were performed for the evaluation of the CoreDryTM and the CoreReaderTM equipment. The statistical analysis consisted of comparison of means of dry mass and Gmb after each drying process. Statistical approaches of comparing means by Analysis of Variance (ANOVA) for more than two groups of data and ttest for two groups were used throughout the analysis. PHASE I COREDRYTM Dry mass of the sample was used for the evaluation of the CoreDryTM as Gmb is directly related to dry mass and the statistical output is no different than using Gmb. Gmb is the dry mass divided by a constant, equal to ‘SSD massSubmerged mass’, so the distribution of data would be the same. ANOVA with Duncan’s multiple range test, paired ttest and comparisons to the standard precision statements were used as analytical tools for the evaluation of the CoreDryTM apparatus. For analysis purposes, data are grouped into two categories, namely lab compacted samples and field cores. . 48 ANOVA with Duncan’s Test Lab Compacted Samples The lab compacted samples have four sets of Gmb and consequently dry masses which are referred to as methods. The dry masses and their notation are as follows: i) Initial dry mass ( Initial dry) ii) Dry mass after CoreDry (CoreDryTM) iii) Dry mass after slow oven drying ( Slow oven) iv) Dry mass after fast oven drying ( Fast oven) For the evaluation of drying efficiency of CoreDryTM apparatus using lab compacted samples, the dry mass by CoreDryTM is compared with initial dry mass (dry mass after cooling to room temperature), dry mass after slow oven drying and dry mass after fast oven drying. The S3 and S4 mixes consists of samples with two different heights, one 95 mm and 115 mm. The SMA samples were all 115 mm high. For effective comparisons, samples of approximately equal dry mass are necessary. Therefore, ANOVA with Duncan’s multiple range tests are performed for each group for the lab compacted samples, by height. The results of ANOVA with Duncan’s multiple range tests are presented in tables 5.1 and 5.2 for group A samples and in tables 5.3 and 5.4 for group B samples. The ANOVA indicates that there is no statistical difference between initial dry, CoreDryTM, slow oven and fast oven dry mass at a confidence limit of 95% (α = 0.05). The means and results from Duncan’s multiple range tests confirm the results. 49 TABLE 5.1. ANOVA Test Result, Group A, Height=95mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 1 459432.68 459432.68 13635.30 <0.0001 Method 2 45.01 22.51 0.67 0.5250 Mix*Method 2 11.50 5.75 0.17 0.8445 Duncan Grouping* Mean Dry Mass N Method A 3740.4 8 Slow oven A 3737.8 8 Fast oven A 3737.2 8 Initial dry * Means with the same letter are not significantly different. TABLE 5.2. ANOVA Test Result, Group A, Height=115mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 1125034.80 562517.40 9204.86 <0.0001 Method 2 11.49 5.75 0.09 0.9104 Mix*Method 4 8.58 2.15 0.04 0.9976 Duncan Grouping* Mean Dry Mass N Method A 4753.4 22 Slow oven A 4752.7 22 Initial dry A 4752.4 22 Fast oven * Means with the same letter are not significantly different. TABLE 5.3. ANOVA Test Result, Group B, Height=95mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 1 439508.53 439508.53 3762.78 <0.0001 Method 2 3.06 1.53 0.01 0.9870 Mix*Method 2 0.05 0.02 0.00 0.9998 50 Duncan Grouping* Mean Dry Mass N Method A 3736.9 8 CoreDryTM A 3736.2 8 Initial dry A 3736.1 8 Fast oven * Means with the same letter are not significantly different. TABLE 5.4. ANOVA Test Result, Group B, Height=115mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 1106003.14 553001.57 14682.80 <0.0001 Method 2 1.10 0.55 0.01 0.9855 Mix*Method 4 0.72 0.18 0.00 1 Duncan Grouping* Mean Dry Mass N Method A 4756.2 21 CoreDryTM A 4756.0 21 Initial dry A 4755.7 21 Fast oven * Means with the same letter are not significantly different. The following figures, figure 5.1 and 5.2, show the interval plot for the mean dry masses and 95% confidence interval for group A and B lab compacted samples, respectively. 51 Initial dry mass Slow oven Core Dry Fast Oven 4700 4600 4500 4400 4300 Dry mass 4481.93 4483.26 4482.39 4481.8 Interval plot for means 95% CI for the Mean FIGURE 5.1 Interval plot for lab compacted samples (Group A). Initial dry mass Slow oven Core Dry Fast Oven 4700 4600 4500 4400 4300 Dry mass 4474.71 4474.61 4475 4474.44 95% CI for the Mean Interval Plot for means FIGURE 5.2 Interval plots for lab compacted samples (Group B). 52 The Duncan’s multiple range test result presented in tables 5.1 and 5.2 for group A samples, and presented in table 5.3 and 5.4 for group B samples, show that the mean is same for all methods. ANOVA results show that there is no significant interaction of mix type on methods. The mean of initial dry, slow oven, and fast oven dry masses for group A are statistically the same and the mean of initial dry, CoreDryTM, and fast oven dry masses are the same for group B samples. The methods are significantly different by mix which is due to the effect of Gsb on dry mass. The Gsb, and consequently dry mass, can be different for different mixes. The results show that the CoreDryTM method works well for effective drying of lab compacted samples and gives statistically similar results to the oven drying methods of AASHTO T166 and to the initial dry mass. Field Cores Field cut cores have only three dry masses; namely slow oven, CoreDryTM and fast oven which are considered as methods for the statistical analysis. Two different sizes of cores were used in the testing, 100 mm and 150 mm and hence, in the analysis. The ANOVA and Duncan’s tests were performed by group, and the interaction of diameter on methods was checked. The ANOVA and Duncan’s multiple range test results for group A are presented in table 5.5 and the test result for group B are presented in table 5.6. The ANOVA results show the means are same for all methods at a confidence interval of 95 % (α = 0.05). 53 TABLE 5.5. ANOVA Test Result for Field Cores, Group A, (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Diameter 1 52062781.14 52062781.14 101.19 < 0.0001 Method 2 62.28 31.14 0.00 0.9999 Diameter*Method 2 1.95 0.98 0.00 1.0000 Duncan Grouping* Mean Dry Mass N Method A 1879.06 103 Slow oven A 1878.56 103 Core Dry A 1877.77 103 Fast oven * Means with the same letter are not significantly different. TABLE 5.6. ANOVA Test Result for Field Cores, Group B, (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Diameter 1 51440952.65 51440952.65 101.19 < 0.0001 Method 2 105.07 75.62 0.00 0.9999 Diameter*Method 2 0.64 0.32 0.00 1.0000 Duncan Grouping* Mean Dry Mass N Method A 1885.08 116 CoreDryTM A 1883.96 116 Slow oven A 1883.51 116 Fast oven * Means with the same letter are not significantly different. The interval plots for the mean dry mass and 95% confidence interval for group A and B field core samples are presented in figure 5.3 and 5.4, respectively. 54 S low oven Core Dry Fast Oven 2050 2000 1950 1900 1850 1800 1750 1700 Dry mass 1879.06 1878.56 1877.83 Inte rplot for me ans 95% CI for the Mean FIGURE 5.3 Interval plot for field cores (Group A). Slow oven Core Dry Fast Oven 2050 2000 1950 1900 1850 1800 1750 1700 Dry mass 1883.96 1885.08 1883.51 Interval plot for means 95% CI for the Mean FIGURE 5.4 Interval plot for field cores (Group B). 55 The ANOVA and Duncan’s multiple range test results presented in tables 5.5 and 5.6 show that slow oven, CoreDryTM and fast oven dry mass are statistically similar. The ANOVA results also indicate that there is no significant interaction of diameter on methods. The means are statistically different for the two different diameters, which were expected. Based on the ANOVA test results, CoreDryTM produces similar results to the slow and fast oven drying methods for field cores which have greater water absorption than lab compacted samples. Paired tTest Lab Compacted Samples The ANOVA test with Duncan’s multiple range test showed that there was no statistical difference among the methods i.e. initial dry, CoreDryTM, slow oven and fast oven dry mass, and hence the Gmb, for lab compacted samples. When the same set of data was analyzed using a one tail paired ttest for two sample means, a statistical difference at a confidence limit of 95% (α = 0.05) was observed. The onetailed paired ttest was used because the dry mass after a drying method is less than or equal to the dry mass after previous drying. The paired ttest results are presented in table 5.7. 56 TABLE 5.7. Paired ttest Result for Lab Compacted Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Height Initial and Slow 4.39 1.89 1.6E03 Not same. 95 mm, Gr. A Slow and Core 4.33 1.89 1.7E03 Not same. Slow and Fast 4.31 1.89 1.8E03 Not same. Initial and Core 8.71 1.89 2.6E05 Not same. 95 mm, Gr. B Core and Slow 4.53 1.89 1.4E03 Not same. Core and Fast 5.24 1.89 6.0E04 Not same. Initial and Slow 2.84 1.86 1.1E02 Not same. 115 mm, Gr. A Slow and Core 2.24 1.86 2.8E02 Not same. Slow and Fast 2.28 1.86 2.6E02 Not same. Initial and Core 3.21 1.86 6.2E03 Not same. 115 mm, Gr. B Core and Slow 2.58 1.86 1.6E02 Not same. Core and Fast 2.82 1.86 1.1E02 Not same. Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass According to the paired ttest results presented in table 5.7, all methods are statistically different. Hence, the CoreDryTM apparatus does not produce similar dry mass as obtain from slow oven or fast oven drying methods for laboratory compacted samples. Table 5.7 also indicates that slow oven dry mass is statistically different than rest of the methods. The statistical difference between the methods in paired ttest is due to the power of the paired ttest compared to the ANOVA (ftest). Field Cores The ANOVA test with Duncan’s multiple range tests showed no statistical difference among all of the methods i.e. CoreDryTM, slow oven and fast oven dry mass for field core samples. When the same set of data was analyzed using a one tail paired ttest for two sample means, a statistically significant difference at a confidence limit of 95% (α = 0.05), was found . The paired ttest results are presented in table 5.8. 57 TABLE 5.8. Paired ttest Result for Field Core Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Group Gr. A Slow and Core 4.36 1.66 1.5E05 Not same. Slow and Fast 7.31 1.66 3.1E11 Not same. Gr. B Core and Slow 9.88 1.66 2.4E17 Not same. Core and Fast 10.68 1.66 3.3E19 Not same. Note: Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass The statistical difference between the methods was found when compared by paired ttest for field cores. All of the methods are statistically different. Hence, the CoreDryTM apparatus does not produce similar dry mass as obtain from slow oven or fast oven drying methods for field cut core samples. Practical Significance Lab Compacted Samples Sometimes, statistically similar results may have a practical difference and statistically different results may not have any practical difference. To evaluate the practical differences among methods, the difference in means between consecutive methods were calculated and compared with the AASHTO T166 requirement for dry state of mass, which is mass loss less than 0.05 % of total mass. The results are presented in table 5.9 for lab compacted samples. The results show that the difference is less than 0.05 percent. Therefore, no practical difference was found for lab compacted samples. The dry mass obtained from CoreDryTM apparatus can be used for laboratory analysis of HMA samples. 58 TABLE 5.9. Practical Significance of the Test Result for Lab Compacted Samples Sample Type Gr. Method Mean dry mass Comparison between Mean % difference Remarks Initial 4472.6 Initial Vs Slow 0.031 No difference Slow 4474.0 Slow Vs Core 0.020 No difference Core 4473.1 Slow Vs Fast 0.034 No difference A Fast 4472.5 Initial 4464.3 Initial Vs Core 0.007 No difference Core 4464.6 Core Vs Slow 0.009 No difference Slow 4464.2 Core Vs Fast 0.006 No difference Lab Compacted B Fast 4464.0 Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass Field Cores To evaluate the practical differences among methods for field cores, the same procedure used for lab samples was followed. The mean difference between consecutive methods were calculated and compared with the AASHTO T166 requirements for dry state of mass, which is mass loss less than 0.05 % of total mass, as in case of lab compacted samples. The results are presented in table 5.10. 59 TABLE 5.10. Practical Significance of the Test Result for Field Cores Sample Type Gr. Method Mean dry mass Comparison between Mean % differenc e Remarks Slow 1813.3 Slow Vs Fast 0.050 No difference Core 1813.1 Core Vs Fast 0.039 No difference Fast 1812.4 Slow Vs Core 0.011 No difference A Core 1758.6 Core Vs Fast 0.045 No difference Slow 1757.9 Slow Vs Fast 0.006 No difference Field Cores B Fast 1757.8 Core Vs Slow 0.040 No difference Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass The difference between the methods was equal to or less than 0.05 %. Therefore; there is no practical difference between the slow and fast method and between CoreDryTM and fast method. The CoreDryTM can be used to determine the dry mass for Gmb determination. PHASE II COREREADERTM This phase of the analysis is the evaluation of CoreReaderTM apparatus. The analysis in this phase includes comparison of the Gmb obtained from CoreReaderTM to Gmb obtained by conventional water displacement methods of AASHTO T166. This was accomplished by the statistical comparison of Gmb obtained from CoreReaderTM to the Gmb obtained by conventional AASHTO T166 methods and the Gmb obtained from the CoreDryTM dry mass. To analyze the comparisons between the methods, ANOVA with Duncan’s multiple range tests and paired ttests were used throughout the analysis. In addition, if the CoreReaderTM Gmb was found different than the Gmb obtained from 60 water displacement method, an attempt will be made to develop a correlation. For the effective analysis and correlation development, lab compacted and field cores are treated separately, similar to phase I analysis. ANOVA with Duncan’s Test Lab Compacted Samples For the lab compacted samples, the dry mass used in phase I were used to calculate the Gmb in AASHTO T166 methods. The lab compacted samples have five sets of Gmb. The five categories and their notations for analysis are as follow: i) AASHTO T166 Gmb( T166) ii) CoreDryTM Gmb (CoreDryTM) iii) Slow oven Gmb ( Slow oven) iv) Fast oven Gmb ( Fast oven) v) CoreReaderTM Gmb (CoreReaderTM) In above categories, T166 Gmb is the conventional bulk specific gravity of lab compacted samples calculated using the volume obtained by water displacement method and initial dry mass of sample before submerging in water in accordance to AASHTO T166. Similarly, CoreDryTM, Slow oven and Fast oven Gmb are obtained by using the volume by water displacement and dry mass after each respective method. An ANOVA with Duncan’s multiple range test were performed for the whole set of data for each group (Group A and Group B) of lab compacted samples. The results of ANOVA with Duncan’s multiple range tests were performed at a confidence limit of 95% (α = 0.05). The results for lab compacted samples for group A and group B are 61 presented in tables 5.11 and 5.12, respectively. The results show that CoreReaderTM Gmb is statistically different from the other test methods. ANOVA results show there is no interaction of type of mix on methods. The data in this phase need not to be analyzed by height as analysis is performed for Gmb, which normalizes the dry mass data. TABLE 5.11. ANOVA Test Result for Lab Compacted Samples, Group A (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 0.31931 0.15966 97.41 < 0.0001 Method 3 0.02497 0.00832 5.08 0.0025 Mix*Method 6 0.00132 0.00022 0.13 0.9916 Duncan Grouping* Mean Gmb N Method A 2.356 30 Slow oven A 2.355 30 Fast oven A 2.355 30 T166 B 2.320 30 CoreReaderTM * Means with the same letter are not significantly different. TABLE 5.12. ANOVA Test Result for Lab Compacted Samples, Group B (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 0.27770 0.13885 77.32 < 0.0001 Method 3 0.02012 0.00671 3.74 0.0135 Mix*Method 6 0.00027 0.00005 0.03 0.9999 Duncan Grouping* Mean Gmb N Method A 2.367 29 CoreDryTM A 2.366 29 T166 A 2.366 29 Fast oven B 2.336 29 CoreReaderTM * Means with the same letter are not significantly different. 62 The ANOVA test results and the Duncan’s multiple range tests presented in tables 5.11 and 5.12 show that Gmb obtained by CoreReaderTM is statistically different than Gmb obtained by water displacement methods. The Gmbs are different for mix type but there is no significant interaction on methods, therefore, it was not necessary to perform the ANOVA by mix type. Field Cores Field cores consist of four types of Gmb namely, CoreReaderTM Gmb, slow oven Gmb, CoreDryTM, and fast oven Gmb. To compare the Gmb by CoreReaderTM, ANOVA with Duncan’s multiple range test was used and the four Gmbs mentioned above were compared. In this case, there is no need to analyze the data by diameter as calculation of Gmb normalizes the data. Therefore, oneway ANOVA with Duncan’s multiple range tests at a confidence limit of 95% (α = 0.05) was performed for group A and group B samples. The test results are presented in tables 5.13 and 5.14 for group A and B field cores, respectively. TABLE 5.13. ANOVA Test Result for Field Cores, Group A (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Method 2 0.13106 0.06553 3.13 0.0451 Duncan Grouping* Mean Gmb N Method A 2.292 103 Slow oven A 2.269 103 Fast oven B 2.242 103 CoreReaderTM * Means with the same letter are not significantly different. 63 TABLE 5.14 ANOVA Test Result for Field Cores, Group B (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Method 2 0.14853 0.07427 19.48 <0.001 Duncan Grouping* Mean Gmb N Method A 2.301 116 CoreDryTM A 2.301 116 Fast oven B 2.257 116 CoreReaderTM * Means with the same letter are not significantly different. The ANOVA test with Duncan’s multiple range test results showed CoreReaderTM Gmb is statistically different than other methods for both groups of field core samples. The Gmb obtained from slow oven, CoreDryTM and fast oven drying were found statistically same, which indicates no difference in these methods, as found in the phase I analysis. Paired tTest Lab Compacted Samples The paired ttest for two sample means between CoreReaderTM Gmb and either AASHTO T166 Gmb or fast oven Gmb, in case of lab compacted samples, showed CoreReaderTM Gmb is statistically different. The one tail paired ttest at a confidence limit of 95% (α = 0.05) for lab compacted samples is presented in table 5.15. 64 TABLE 5.15. Paired ttest Result for Lab Compacted Samples Group Comparison between tstatistic tcritical P value Comments on means By Group Gr. A CR and T166 12.40 1.70 4.1E13 Not same. CR and Fast 12.28 1.70 2.6E13 Not same. Gr. B CR and T166 10.68 1.70 1.1E11 Not same. CR and Fast 10.66 1.70 1.1E11 Not same. By Height 115 mm, Gr. A CR and T166 6.32 1.86 1.1E04 Not same. CR and Fast 6.23 1.86 1.2E04 Not same. 115 mm, Gr. B CR and T166 4.53 1.86 9.6E04 Not same. CR and Fast 4.54 1.86 9.6E04 Not same. 95 mm, Gr. A CR and T166 12.97 1.89 1.9E06 Not same. CR and Fast 13.55 1.89 1.4E06 Not same. 95 mm, Gr. B CR and T166 8.1721 1.89 4.0E05 Not same. CR and Fast 8.2001 1.89 3.9E05 Not same. Note: CR: CoreReaderTM Gmb; Fast: Fast oven Gmb; T166: AASHTO T166 Gmb. Field Cores The same approach for comparison of CoreReaderTM Gmb and fast oven Gmb was applied to the field cores. The one tail paired ttest results for field cores at a confidence limit of 95% (α = 0.05) are presented in table 5.16. The paired ttest results show that there is a statistical difference between Gmb obtained from CoreReaderTM and AASHTO T166. 65 TABLE 5.16. Paired ttest Result for Field Core Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Group Gr. A CR and Fast 1.2765 1.6599 0.1023417 Are same Gr. B CR and Fast 9.3211 1.6582 4.953E16 Not same. CR and F By ast 19.859 1.666 1.873E31 Not same. Diameter 150 mm, Gr. A CR and Fast 7.6961 1.6628 1.084E11 Not same. 150 mm, Gr. B CR and Fast 12.481 1.7011 2.933E13 Not same. 100 mm, Gr. A CR and Fast 7.1918 1.7011 3.963E08 Not same. 100 mm, Gr. B Note: CR: CoreReaderTM Gmb; Fast: Fast oven Gmb; The paired ttest for lab compacted samples showed a statistical difference between CoreReaderTM Gmb and the rest of the methods. For field cores, the CoreReaderTM Gmb and fast oven Gmb are statistically similar for Group A cores when both 100 and 150 mm diameter samples are analyzed together. When the field cores were tested for paired ttest by breaking into two groups by diameter, CoreReaderTM Gmb was found to be different than fast oven Gmb. Practical Significance Lab Compacted Samples Practical significance is as important as statistically similar results. Test results can have no practical difference and show statistical difference. To evaluate the practical differences between AASHTO T166 Gmb and CoreReaderTM Gmb, the AASHTO precision guideline was used. According to AASHTO T166 (3), the difference between 66 Gmb by two consecutive tests should not be greater than 0.02, the acceptable limit for laboratory Gmb determination. In this case, only AASHTO T166 Gmb is used to compare with CoreReaderTM, as previous section has already shown that AASHTO T166, slow oven, CoreDryTM, and fast oven Gmb are similar. Practical significance check is presented in table 5.17 for lab compacted samples. Results show that the difference in Gmb exceeds the acceptable limit for test results and, therefore, the methods produce different results. TABLE 5.17. Practical Significance of the Test Result for Lab Compacted Samples Sample Type Gr. Method Mean Gmb Comparison between Mean differenc e Remarks AASHTO T166 2.355 A CoreReaderTM 2.320 AASHTO T166 and CoreReaderTM 0.035 Are different. Lab Samples AASHTO T166 2.367 B CoreReaderTM 2.336 AASHTO T166 and CoreReaderTM 0.031 Are different. Field Cores The same approach of evaluating the practical significance of lab compacted samples was applied to the field cores. The mean difference between the CoreReaderTM and fast oven Gmb were calculated and compared with the AASHTO T166 precision requirement of a difference of less than 0.02. The results are presented in table 5.18. 67 TABLE 5.18. Practical Significance of the Test Result for Field Core Samples Sample Type Gr. Method Mean Gmb Comparison between Mean difference Remarks CoreReaderTM A 2.241 Fast oven 2.269 CoreReaderTM and Fast oven 0.028 Are different. Field cores CoreReaderTM 2.257 B Fast oven 2.305 CoreReaderTM and Fast oven 0.048 Are different. For field cores, the CoreReaderTM Gmb produces different results than AASHTO T166 fast oven Gmb. The ANOVA with Duncan’s multiple range tests and paired ttest showed CoreReaderTM Gmb is different than Gmb obtained from AASHTO T166 methods and CoreDryTM apparatus for both lab compacted and field core samples. The CoreReaderTM Gmb is outside the acceptable range of two results listed in AASHTO T166. Thus, the above tests indicate that the CoreReaderTM apparatus does not produce the same results as AASHTO T166. PHASE III Effect of Parallel Faces on CoreReaderTM Gmb The test procedure for the CoreReaderTM says sample ends need to be parallel with smooth edges. To evaluate the effect of parallel faces on CoreReaderTM Gmb, field cores with one end uneven or irregular were first tested in CoreReaderTM and again with both faces parallel by sawing one side. A less powerful ttest assuming equal variance, which is the same as ftest for two methods, and the more powerful paired t test for two sample means, were used to evaluate the difference. Table 5.19 shows the comparison using ttest and paired ttest at a confidence limit of 95 % (α = 0.05). 68 TABLE 5.19. ttest Results for Effect of Parallel Faces on CoreReaderTM Gmb Type of test tstatistic tcritical Pvalue Comments on means ttest, assuming equal variances 1.608 1.661 0.0548 Means are same Paired ttest, two sample for means 2.583 1.653 0.0057 Means are not same. The ttest showed there is no statistical difference between Gmb before and after sawing the cores. The paired ttest, which is a more powerful test than the ttest, showed that there is a significant difference between the two Gmbs. The mean and standard deviation of the CoreReaderTM Gmb for cores with one face not smooth (i.e. having higher heights) is 2.249 and 0.1169 whereas for both faces smooth (i.e. having smaller heights) are 2.279 and 0.067. The difference in means value is 0.030, which is greater than the acceptable range of two results of 0.02, as listed in AASHTO T166. In this case the samples with both faces parallel also had a lower standard deviation, 0.067 compared to 0.1169. It appears that the parallel face requirement for CoreReaderTM testing is justified. Figure 5.5 indicates that most of the data are above the line of equality, indicating that having both faces parallel results in slightly higher Gmb values. 69 CRD Gmb before vs CRD Gmb after sawing 2.05 2.1 2.15 2.2 2.25 2.3 2.35 2.4 2.05 2.15 2.25 2.35 CRD Gmb, before sawing CRD Gmb, after sawing .. After sawing Linear (Line of equality) FIGURE 5.5 Before vs. after sawing plot for CoreReaderTM Gmb. CORRELATION BETWEEN COREREADERTM AND AASHTO T166 Gmb Lab Compacted Samples The previous statistical analysis showed that CoreReaderTM Gmb is statistically different than AASHTO T166 Gmb. However, this does not mean that the CoreReaderTM cannot be successfully used to determine the Gmb of HMA samples. Many state DOTs allow the use of nuclear and/or non nuclear density meters to determine the inplace density of HMA pavements if a correlation is established between Gmb from cores of the pavement and gauge results. To develop the correlations between CoreReaderTM Gmb and AASHTO T166, Gmb the field cores and lab samples were used. The lab compacted 70 S3 and S4 mixes were compacted to two VTM contents only, and cannot be used to establish a correlation. The lab compacted SMA samples contained a wide variation in Gmb, and a meaningful correlation could be developed. The relationship is shown in figure 5.6. The relation has a goodness of fit (R2) of 0.94 indicating that a good approximation of T166 Gmb can be made. AASHTO T166 Gmb can be approximated using the CoreReaderTM Gmb, using the following relationship. T166= 0.7469 * CR + 0.6244 Where, T166= AASHTO T166 Gmb CR= CoreReaderTM Gmb Lab Mix (SMA) y = 0.7469x + 0.6244 R2 = 0.9359 2.220 2.240 2.260 2.280 2.300 2.320 2.340 2.360 2.380 2.400 2.420 2.220 2.270 2.320 2.370 2.420 CoreReader TM Gmb T166 Gmb . T 166 gmb Line of equality FIGURE 5.6 Correlation of T166 Gmb and CoreReaderTM Gmb for SMA. 71 Field Cores For field cores, the CoreReaderTM Gmb was found to be statistically different from AASHTO T166 Gmb by both the ftest and ttest. A regression plot of CoreReaderTM and AASHTO T166 Gmb (fast oven Gmb) for 100 mm and 150 mm samples together, is presented in figure 5.7. Field cores y = 0.8753x + 0.3266 R2 = 0.8601 2.000 2.050 2.100 2.150 2.200 2.250 2.300 2.350 2.400 2.450 2.000 2.100 2.200 2.300 2.400 CoreReader TM Gmb Fast oven Gmb . Fast oven Gmb Line of equality FIGURE 5.7 Correlation of T166 fast oven Gmb and CoreReaderTM Gmb for 100 mm and 150 mm field cores. The value of T166 Gmb (fast oven Gmb) using CoreReaderTM Gmb for field cores can be approximated, using the following relationship, T166 fast oven Gmb = 0.8753 * CR + 0.3226 Where, CR= CoreReaderTM Gmb. The relationship has a goodness of fit (R2) of 0.86. 7 2 CHAPTER 6 CONCLUSIONS AND RECOMMEDDATIONS CONCLUSION Based on the test results obtained and analysis of the test data, the following conclusions were made for phase I, phase II and phase III evaluations. Phase I CoreDryTM 1. The ANOVA test, which is considered a less powerful test than paired ttest, showed that initial dry mass, slow oven dry mass, dry mass after CoreDryTM and fast oven dry mass are statistically similar. ANOVA results also indicated that there is no significant interaction between type of mix and sample diameter on drying methods. This was true for both laboratory compacted and field core samples. 2. Paired ttest analysis showed that the CoreDryTM, slow oven and fast oven dry masses are not statistically similar. 3. Besides the statistical analysis, practical significance of the difference in dry masses was checked according to the AASHTO T166 requirement of a mass loss of less than 0.05 % between the two consecutive drying operations. There was no practical difference found between the slow and fast methods and between the CoreDryTM and fast method for both lab compacted and field core samples. 7 3 4. Based on the statistical and practical analysis of the test data, the CoreDryTM can be considered as equivalent to the AASHTO T166 method A and method C, which are slow oven drying method and fast oven drying method, respectively. Phase II CoreReaderTM 1. The ANOVA ftest and paired ttest analysis showed that the Gmb obtained by CoreReaderTM apparatus is statistically different than Gmb obtained by AASHTO T166 methods at a significance level of 95%. 2. The CoreReaderTM Gmb was also statistically different than the Gmb obtained by using the dry mass obtained from the CoreDryTM. 3. A practical difference in Gmb greater than 0.020, was also found between the CoreReaderTM Gmb and Gmb obtained from AASHTO T166 methods. 4. Based on the statistical and practical analysis, the CoreReaderTM apparatus cannot be considered as a direct substitute for the AASHTO T166 methods of Gmb determination. Detail study is required before considering it as an alternative method of Gmb determination. 5. A correlation similar to what is used for field nuclear density devices can be used to calculate AASHTO T166 Gmb using CoreReaderTM Gmb for lab compacted and field core samples. Phase III Effect of Parallel Faces on CoreReaderTM Gmb To check the effect of irregular and uneven faces on CoreReaderTM Gmb, paired ttest, and ttest assuming equal variances were used. Paired ttest showed that there is a significant difference between the two Gmbs whereas ttest showed that there is not an effect of unparallel faces on CoreReaderTM Gmb. The difference in mean value was out 7 4 of acceptable limit of 0.020, as listed in ASHTO T166. Hence, there is significant effect of uneven and unparallel faces on CoreReaderTM Gmb and the requirement for smooth parallel faces should be followed. RECOMMENDATIONS 1. The CoreDryTM apparatus can be used for the drying of lab compacted as well as field core samples for the Gmb determination. 2. CoreReaderTM apparatus did not produce similar results to AASHTO T166. If desire to use, correlations should be developed similar to those used when using the filed nuclear density devices. 3. It is necessary to saw the field core samples to make its faces smooth and parallel for the Gmb determination by CoreReaderTM apparatus. 7 5 REFERENCES 1. Application Brief Troxler Model 3660, CoreReaderTM. Laboratory Nuclear Density Device, Troxler, http://www.troxlerlabs.com/pdf%20files/3660appbrief.pdf. Accessed July 16 2007. 2. User Guide, InstroTek® CoreDryTM Apparatus, http://www.instrotek.com/coredry.htm. Accessed July 15 2007. 3. “Bulk Specific Gravity of Compacted HotMix Asphalt Using Saturated Surface Dry Specimens, AASHTO Designation: T166.”Standard Specifications for Transportation Materials and Methods of Sampling and Testing, Twentyfifth Edition, Part 2A, Tests, American Association of State Highway and Transportation officials, Washington, D.C., 2005. 4. “Standard Test Method for Bulk Specific Gravity and Density of NonAbsorptive Compacted Bituminous Mixtures”, ASTM Designation: D2726. Annual Book of ASTM Standards, Section four, Volume 05.03., American Society for Testing and Materials, West Conshohocken, PA., 2005. 5. Hall, Kevin D., Kevin, “Evaluation of Drying Efficiency for HotMix Cores Using Vacuum Drying Method.” Compendium of Papers, 86th Annual Meeting of the Transportation Research Board. CDROM. Transportation Research Board, National Research Council, Washington, D.C., January 2007. 6. Troxler CoreReaderTM Model 3660. www.troxlerlabs.com. Accessed July 16 2007. 7. Retzer, N., “Review and Research of Instrotek’s CoreDry® Report”, Materials and Geotechnical Branch, Colorado Department of Transportation, Denver, Colorado, 2006. 8. Williams, Stacy G., “Bulk Specific Gravity Measurements of 25.0 mm and 37.5 mm CoarseGraded Superpave Mixes.” Compendium of Papers, 86th Annual Meeting of the Transportation Research Board. CDROM. Transportation Research Board, National Research Council, Washington, D.C., January 2007. 9. Malpass and Khosla, “Evaluation of Gamma Ray Technology for the Measurement of Bulk Specific Gravity of Compacted Asphalt Concrete Specimens.” Journal, Association of Asphalt paving Technologists, Association of Asphalt Paving Technologists. Vol. 70, p352, 2001 VITA Gyanendra Pokhrel Candidate for the Degree of Master of Science Thesis: VALIDATION OF COREDRYTM AND COREREADERTM APPRATUS Major Field: Civil Engineering Biographical: Personal Data: Born on December 28th, 1980 in Nepal. Education: Completed the requirements for the Master of Science in Civil Engineering at Oklahoma State University, Stillwater, Oklahoma in December, 2007. Experience: Research Assistant, Department of Civil Engineering, Oklahoma State University, Stillwater, February 2006December 2007 Professional Memberships: Member of Honor society, Phi Kappa Phi, Oklahoma State University. Member of American Society of Civil Engineers, Student Chapter at Oklahoma State University. Member of Nepal Engineering Council, Nepal. ADVISER’S APPROVAL: Dr. Stephen A. Cross Name: Gyanendra Pokhrel Date of Degree: December, 2007 Institution: Oklahoma State University Location: Stillwater, Oklahoma Title of Study: VALIDATION OF COREDRYTM AND COREREADERTM APPARATUS Pages in Study: 75 Candidate for the Degree of Master of Science Major Field: Civil Engineering Scope and Method of Study: The evaluation of CoreDryTM, and CoreReaderTM apparatus was completed based on the test results of laboratory prepared ODOT S3, S4 and SMA mixes and field cores of 100 mm and 150 mm. The CoreDryTM apparatus was evaluated by comparing the dry mass obtained using the CoreDryTM apparatus with dry mass obtained by AASHTO T166 drying methods. The evaluation of CoreReaderTM was completed by comparing the Gmb obtained using CoreReaderTM apparatus and Gmb obtained by AASHTO T166 procedures. The comparison of means of dry masses and Gmbs was performed by statistical tests such as ANOVA, paired ttest, and ttest. Findings and Conclusions: The CoreDryTM apparatus can be used for the drying of lab compacted as well as field core samples for the Gmb determination. CoreReaderTM apparatus did not produce similar results to AASHTO T166. If desire to use, correlations should be developed similar to those used when using the filed nuclear density devices. It is necessary to saw the field core samples to make its faces smooth and parallel for the Gmb determination by CoreReaderTM apparatus.
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Title  Validation of the Coredry(Tm) and Corereader(Tm) Appratus 
Date  20071201 
Author  Pokhrel, Gyanendra 
Department  Civil & Environmental Engineering 
Document Type  
Full Text Type  Open Access 
Note  Thesis 
Rights  © Oklahoma Agricultural and Mechanical Board of Regents 
Transcript  VALIDATION OF THE COREDRYTM AND COREREADERTM APPRATUS By GYANENDRA POKHREL Bachelor of Science in Civil Engineering Nepal Engineering College Bhaktapur, Nepal 2004 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of MASTER OF SCIENCE December, 2007 i i VALIDATION OF THE COREDRYTM AND COREREADERTM APPRATUS Thesis Approved: Dr. Stephen A. Cross Thesis Adviser Dr. Rifat Bulut Dr. Hyung Seok(David) Jeong Dr. A. Gordon Emslie Dean of the Graduate College ii i TABLE OF CONTENTS Chapter Page 1. INTRODUCTION .....................................................................................................1 PROBLEM STATEMENT......................................................................................1 OBJECTIVES..........................................................................................................2 SCOPE.....................................................................................................................3 2. REVIEW OF LITERATURE………………………………………………………4 BULK SPECIFIC GRAVITY OF ASPHALT MIXES (Gmb) ...............................4 AASHTO T166........................................................................................................5 Method A ..............................................................................................................5 Method B ..............................................................................................................5 Method C ..............................................................................................................6 ASTM D2726...........................................................................................................6 COREDRYTM ..........................................................................................................7 COREREADERTM...................................................................................................9 PREVIOUS RESEARCH......................................................................................11 CoreDryTM............................................................................................................11 CoreReaderTM ......................................................................................................13 SUMMARY...........................................................................................................14 3. TEST PLAN……………………………………………………………………….15 MATERIALS.........................................................................................................15 Lab Samples.........................................................................................................15 S3 and S4 Mixes ................................................................................................16 Stone Matrix Asphalt (SMA) Mix .....................................................................17 Field Cores ...........................................................................................................18 TEST PROCEDURE .............................................................................................19 Lab Samples ........................................................................................................19 Group A ...........................................................................................................20 Group B.............................................................................................................20 Field Cores ...........................................................................................................21 Effect of Parallel Faces ........................................................................................22 Before Sawing....................................................................................................22 After Sawing ......................................................................................................22 ANALYSIS............................................................................................................24 iv Phase I CoreDryTM.............................................................................................24 Phase II CoreReaderTM ......................................................................................24 Phase III .............................................................................................................24 4. TEST RESULTS......................................................................................................25 PHASE I COREDRYTM ........................................................................................25 Group A ...............................................................................................................26 Group B................................................................................................................26 PHASE II COREREADERTM................................................................................27 PHASE III ..............................................................................................................27 5. ANALYSIS OF TEST RESULTS..........................................................................47 PHASE I COREDRYTM ........................................................................................47 ANOVA with Duncan’s Test...............................................................................48 Lab Compacted Samples..................................................................................48 Field Cores .......................................................................................................52 Paired tTest .........................................................................................................55 Lab Compacted Samples...................................................................................55 Field Cores ........................................................................................................56 Practical Significance...........................................................................................57 Lab Compacted Samples...................................................................................57 Field Cores ........................................................................................................58 PHASE II COREREADERTM................................................................................59 ANOVA with Duncan’s Test...............................................................................60 Lab Compacted Samples..................................................................................60 Field Cores .......................................................................................................62 Paired tTest .........................................................................................................63 Lab Compacted Samples...................................................................................63 Field Cores ........................................................................................................64 Practical Significance...........................................................................................65 Lab Compacted Samples...................................................................................65 Field Cores ........................................................................................................66 PHASE III ..............................................................................................................67 Effect of Parallel Faces on CoreReaderTM Gmb...............................................67 CORRELATION BETWEEN COREREADERTMAND AASHTO T166 Gmb ...69 Lab Compacted Samples..................................................................................69 Field Cores .......................................................................................................71 6. CONCLUSIONS AND RECOMMENDATIONS ..................................................72 CONCLUSIONS....................................................................................................72 Phase I CoreDryTM..............................................................................................72 Phase II CoreReaderTM .......................................................................................73 Phase III Effect of Parallel Faces on CoreReaderTM Gmb..................................73 v RECOMMENDATIONS.......................................................................................74 REFERENCES ............................................................................................................75 vi LIST OF TABLES Table Page 3.1. Test Specimens of S3 and S4 Mix .....................................................................15 3.2. S3 and S4 Mix Design .......................................................................................16 3.3. Typical Gradation of Aggregate for SMA.........................................................18 4.1. Lab Test Result of Lab Compacted Samples, Phase I, Group A ......................28 4.2. Lab Test Result of Field Cores, Phase I, Group A ............................................29 4.3. Lab Test Result of Lab Compacted Samples, Phase I, Group B ......................32 4.4. Lab Test Result of Field Cores, Phase I, Group B.............................................33 4.5. Lab Test Result of Lab Compacted Samples, Phase II, Group A .....................37 4.6. Lab Test Result of Field Cores, Phase II, Group A ..........................................38 4.7. Lab Test Result of Lab Compacted Samples, Phase II, Group B .....................41 4.8. Lab Test Result of Field Cores, Phase II, Group B ...........................................42 4.9. CoreReaderTM Gmb Before and After Sawing of Field Cores ..........................45 5.1. ANOVA Test Results, Group A, Height= 95 mm, (By Height)........................49 5.2. ANOVA Test Results, Group A, Height= 115 mm, (By Height)......................49 5.3. ANOVA Test Results, Group B, Height= 95 mm, (By Height) ........................49 5.4. ANOVA Test Results, Group B, Height= 115 mm, (By Height) ......................50 5.5. ANOVA Test Results for Field Cores, Group A, (By Group)...........................53 5.6. ANOVA Test Results for Field Cores, Group B, (By Group)...........................53 5.7. Paired ttest Result for Lab Compacted Samples ..............................................56 5.8. Paired ttest Result for Field Core Samples.......................................................57 5.9. Practical Significance of the Test Result for Lab Compacted Samples.............58 5.10. Practical Significance of the Test Result for Field Cores ...............................59 5.11. ANOVA Test Results for Lab Compacted Samples, Group A, (By Group) ...61 5.12. ANOVA Test Results for Lab Compacted Samples, Group B, (By Group) ...61 5.13. ANOVA Test Results for Field Cores, Group A, (By Group).........................62 5.14. ANOVA Test Results for Field Cores, Group B, (By Group).........................63 5.15. Paired ttest Results for Lab Compacted Samples ..........................................64 5.16. Paired ttest Results for Field Core Samples ...................................................65 5.17. Practical Significance of the Test Result for Lab Compacted Samples...........66 5.18. Practical Significance of the Test Result for Field Core Samples ...................67 5.19. ttest Results for the Effect of Parallel Faces on CoreReaderTM Gmb.............68 vii LIST OF FIGURES Figure Page 2.1 InstroTek® CoreDryTM apparatus............................................................................8 2.2 Troxler CoreReaderTM Model 3660.......................................................................10 3.1 Grain size distribution curve of aggregate for S3 and S4 mixes............................17 3.2 Typical grain size distribution curve for SMA mix...............................................18 3.3 Test procedure for lab compacted samples ............................................................21 3.4 Test procedure for field core samples ....................................................................23 5.1 Interval plot for lab compacted samples (Group A) ..............................................51 5.2 Interval plot for lab compacted samples (Group B)...............................................51 5.3 Interval plot for field cores (Group A)...................................................................54 5.4 Interval plot for field cores (Group B) ...................................................................54 5.5 Before vs. after sawing plot for CoreReaderTM Gmb ............................................69 5.6 Correlation of T166 Gmb and CoreReaderTM Gmb for SMA ...............................70 5.7 Correlation of T166 fast oven Gmb and CoreReaderTM Gmb for 100 mm and 150 mm field cores ...............................................................................................71 1 CHAPTER 1 INTRODUCTION PROBLEM STATEMENT The determination of the bulk specific gravity (Gmb) of bituminous paving mixture is an important part of the superpave mix design system and construction quality control/ quality assurance program. The bulk specific gravity is used to determine the air void content (VTM), voids in mineral aggregate (VMA), voids filled with asphalt (VFA) and percent density after compaction of bituminous mixtures. The Gmb of pavement cores are used in determining the percent compaction of hotmix asphalt (HMA) pavements. All of the above parameters are monitored closely during production to ensure satisfactory pavement performance. Problems or errors in measuring the Gmb can lead to pavement distresses such as rutting, stripping, bleeding, cracking, age hardening, and excessive permeability which finally have impact on pavement performance. With the introduction of coarser superpave mixtures and open graded specialty mixes, the ability of current procedures to accurately measure Gmb is being questioned. This is due to increased interconnected voids of coarse and open graded mixes, which can result in overapproximations of density and under approximation of VTM. Repeatability and consistency problem in Gmb test values are also more pronounced for coarse graded mixes. AASHTO T166 is used to determine the Gmb for samples with less than 2 two percent moisture absorption. AASHTO TP69, the CoreLokTM procedure, is recommended for samples with greater than two percent moisture absorption. Troxler® has developed the CoreReaderTM apparatus which can overcome all the drawbacks of AASHTO T166 and AASHTO TP69. The manufacturer claims that this device, when properly calibrated, provides repeatable and accurate measurements that are not operator dependent (1). The Troxler® 3660 CoreReaderTM uses gamma ray technology to determine the density and Gmb of HMA samples without using water displacement methods or dimensional analysis procedures. Initial results indicate that the CoreReaderTM has potential to accurately measure Gmb of HMA samples with interconnected voids (1). An evaluation of the CoreReaderTM could result in a more accurate measurement of Gmb, resulting in improved pavement performance. A second problem with AASHTO T166 is the time it takes to dry the sample and potential damage to the sample caused by drying at elevated temperatures. InstroTek® has developed the CoreDryTM apparatus that dries a core without heat, reducing testing time and allowing further testing of the sample without concern of damage to or artificial hardening of the sample due to heat of drying (2). The test procedure is listed in ASTM D7227. However, there was little published literature verifying that the dry mass determined from CoreDryTM is the same as determined using AASHTO T166. OBJECTIVES There were two main objectives of this study. The first objective was to determine if the Gmb of pavement cores determine using the CoreDryTM apparatus produces statistically similar results to AASHTO T166, resulting is substantial time savings to 3 contractors and for quality control and quality assurance works. The second objective was to determine if the CoreReaderTM produces statistically similar bulk specific gravities to AASHTO T166. If the results are different, correlations will be developed between the CoreReaderTM and AASHTO T166 Gmb. The effect of parallel surface and roughness of sample faces on CoreReaderTM Gmb will also be evaluated. SCOPE As the CoreDryTM and CoreReaerTM apparatus are new in determination of bulk specific gravity of HMA samples, there was little much literature available on the procedures to review. Only guidelines given by manufacturer and three unpublished articles were found and reviewed for this study. For the true comparison of AASHTO T166 Gmb with the Gmb obtained either by CoreDryTM or CoreReaerTM, a wide variety of samples ranging from dense to loose mix is needed. Different mixes with different void contents are necessary to evaluate the efficiency of the apparatus. The test results and analysis were done using lab compacted samples which were limited to ODOT S3, S4 and SMA mixes and field cores of diameter100 mm and 150 mm of unknown volumetric properties. 4 CHAPTER 2 REVIEW OF LITERATURE BULK SPECIFIC GRAVITY OF ASPHALT MIXES (Gmb) AASHTO defines the bulk specific gravity (Gmb) of an asphalt mix as the ratio of the weight in air of a unit volume of material (including both permeable and impermeable voids) at a stated temperature to the weight in air of an equal volume of gasfree distilled water at a stated temperature (3). The accurate measurement of bulk specific gravity (Gmb) of hotmix asphalt (HMA) is critical in mix design and determination of volumetric properties. The accurate determination of Gmb has been a topic of research for many DOTs and agencies for many years. The introduction of Superpave mix design methods in the late 1980’s resulted in the use of more coarse graded mixtures. With the use of coarse graded mixtures, agencies began noticing difficulty in accurately determining the Gmb of these coarse graded HMA mixes. There are several methods available for determination of Gmb of asphalt mixes. Common procedures are SSD method as outlined in AASHTO T166, Height–diameter or dimensional analysis method, CoreReaderTM (using Gamma rays), CoreLokTM (a vacuum sealing device) method as outlined in ASTM D6752 and AASHTO TP 69, and paraffin and Para film methods (AASHTO T275). 5 AASHTO T166 AASHTO T166 outlines the laboratory determination of bulk specific gravity by water displacement. The method consists of determination of dry weight and volume of the lab compacted as well as field core sample. AASHTO T166 uses the following formulas to calculate the bulk specific gravity and percent water absorption of asphalt mixture (1). Where, A= mass in grams of dry specimen in air B= mass in grams of the saturated surfacedry (SSD) specimen in air C= mass in grams of the specimen in water Method A For lab compacted samples, dry mass is the mass of the sample after cooling to room temperature at 25±5ºC (77±9ºF). The determination of the volume of the sample is by water displacement. In this method, the mass of sample immersed in water at 25±1ºC (77±1.8ºF) for 4±1 minute is the submerged mass (C) and the mass of specimen by blotting with a damp towel quickly is the surfacedry mass (B) (3). For filed core samples the dry mass (A) is defined as the mass at which further drying at 52±3ºC (125±5ºF) does not alter the mass by more than 0.05 %. Samples partially saturated with water are dried overnight at 52±3ºC (125±5ºF) and then weighed at twohour drying intervals until the mass loss is less than 0.05 %. Method B This method outlines the measurement of Gmb by volumeter. Method B consists of determining the dry mass (A) of lab compacted sample by cooling to 25±5ºC (77±9ºF) and saturateddry mass (B) by blotting a sample with a damp towel, immersed in water at 6 25±1ºC (77±1.8ºF) for 10 minutes. The mass of the volumeter filled with water at 25±1ºC (77±1.8ºF) (E) is taken and the following formula is used to calculate the Gmb (3). Where, D= mass in grams of the volumeter filled with water at 25±1ºC (77±1.8ºF) E= mass in grams of the volumeter filled with specimen and water at 25±1ºC (77±1.8ºF) A and B are as previously defined. If the percent water absorption is greater than 2 %, AASHTO T166 method B recommends using AASHTO T275 to determine the bulk specific gravity. Method C (Rapid Test) AASHTO T166 Method C outlines the procedure of determining the Gmb of lab compacted and field core samples which have a substantial amount of moisture and are not required for further testing. In this method, the determination of volume is similar to Method A. The only difference in this method is the dry mass (A). The sample is dried at 110±5ºC (230±9ºF) to a constant mass. Constant mass in this case is mass loss does not alter by more than 0.05 percent when weighed at 2hour intervals. The dry mass (A) is the mass of sample at room temperature when mass loss is less than 0.05 % (3). The only disadvantage of this method is it can damage the sample for further testing. ASTM D2726 ASTM D2726 outlines the procedure for determination of Gmb of asphalt mix (4). For the laboratory prepared sample, the dry mass (A), surfacedry mass (B) and submerged mass (C) are determined as in AASHTO T166. For the laboratory drilled and field drilled cores ASTM D2726 recommends drying the sample at 110±5ºC (230±9ºF) to a constant 7 mass. Constant mass in this case is mass loss does not alter by more than 0.1 percent when weighed at 2hour intervals. ASTM D2726 does not allow drying the drilled cores at reduced temperature such as 52ºC (4). COREDRYTM The best method to determine the dry state or constant mass of field or laboratory cut cores is still in question as there are a number of methods available and the accurate determination of the dry mass is necessary in calculating the bulk specific gravity of asphalt mixes. According to InstroTek ® (2), the CoreDryTM apparatus was introduced to overcome the problem. The CoreDryTM system uses high vacuum in conjunction with a thermoelectric cold trap to draw moisture out of a sample, evaporate the moisture, and subsequently condense the moisture in a separate chamber. It provides a constant mass in relatively less time than traditional ovendrying techniques. The vacuum system lowers the vapor pressure in the chamber holding the specimen to draw out and evaporate trapped moisture. As such, the specimen remains at or near room temperature, which helps to retain the HMA characteristics due to prolonged exposure to the heat and oxidation potential present in forceddraft ovens (5). The CoreDryTM is already accepted by ASTM and the test procedure is available as ASTM D7227. The apparatus consists of sample chamber, water trap system and key pad. The apparatus performs a self test when it is started. The operation of CoreDryTM is simple and easy. A sample is placed in the sample chamber and drying operation can be completed by hitting the start button. During the drying operation, the apparatus runs through a series of drying cycles at a reduced pressure until the dry condition is met. The 8 number of cycles depends on the amount of moisture present in sample. The cold trap system collects all the water drawn by vacuum action which needs to remove after each drying operation. Sucking of water from the sample by vacuum action and collecting trapped water in water chamber constitutes a cycle. The apparatus goes through a number of such cycles to remove the water present in sample (2). The CoreDryTM apparatus is shown in figure 2.1 FIGURE 2.1 InstroTek® CoreDryTM apparatus. 9 COREREADERTM The Troxler Model 3660 CoreReaderTM is a laboratory nuclear device used to measure the bulk specific gravity and density of laboratory and field specimens (4). The CoreReaderTM uses gamma rays for determination of the pavement density and bulk specific gravity. The gamma ray method of density measurement is based on the scattering and absorption properties of gamma rays with matter. When a gamma ray source of primary energy in the Compton range is placed near a material, and energy selective gamma ray detector is used for gamma ray counting, the scattered and unscattered gamma rays with energies in the Compton range can be counted exclusively and directly converted to the density or bulk specific gravity of the material (1). CoreReaderTM bulk specific measurement is a non destructive, operator independent test and does not harm the mix property for further testing. CoreReaderTM can be used for hot specimens, resulting in a time saving for cooling of laboratory compacted samples (6). The apparatus consists of sample chamber and key pad. A sample size of 100 mm or 150 mm fits into the sample chamber. The operator selects the sample size and inputs the height of specimen. The manufacturer recommends the input height should be the average height measured at six evenly spaced locations by a caliper having precision of ±0.1mm. The height of the sample should be 110120 mm for 150 mm diameter laboratory sample. Once this information has been entered and the START button pressed, the CoreReaderTM measures the specimen specific gravity (Gmb) and density and displays the results on the screen. If the operator enters a maximum specific gravity (Gmm), it also calculates and displays the air void content (VTM). CoreReaderTM 10 calculates Gmb using the entered height and diameter of the specimen. This requires that specimens need to be parallel with smooth edges for testing. The allowable angle between two faces is 3º. The apparatus needs calibration with the standard set of calibrating cylinders when moved to new place or used after long time (6). The CoreReaderTM apparatus is shown in figure 2.2. FIGURE 2.2 Troxler CoreReaderTM Model 3660. The nondestructive bulk specific gravity (Gmb) determination of laboratory prepared and cored pavement specimens allow for performance tests to be conducted on the same specimens used in the Gmb determinations. In addition to the time savings, more reliable correlation between densities and moduli of specimens may be achieved. Troxler claims the following measurement precision, 11 Repeatability (Single Laboratory) 0.006 Sp. Gravity 6 kg/m3 (0.3744 pcf) Reproducibility (Multi laboratory) 0.009 Sp. Gravity 9 kg/m3 (0.5616 pcf) Troxler also states that the researcher does not have to prepare as many sample replicates to measure both volumetric and mechanical properties (1). PREVIOUS RESEARCH As both products, the CoreDryTM and CoreReaderTM are only few years old, there has not been much research on the devices. There were few published articles on CoreDryTM and CoreReader TM found in the literature. Only three published articles, one on CoreReaderTM and two on CoreDryTM, were found. Although there is not much published data on CoreDryTM, it has been accepted for use and the procedure is found in ASTM D7227. CoreDryTM In 2006, Kevin D. Hall (5) performed a study to investigate the ability of the CoreDryTM vacuum drying system to provide consistent and accurate estimates of constant mass for compacted HMA specimens. The study focused on the efficacy of the drying systemprovision of constant mass condition for a range of initial saturation conditions, and the practicality of the drying system, regarding the time required for obtaining the constant mass determination. A total of 29 gyratory compacted specimens of three different aggregate sizes (NMAS) were used in the analysis. Two different sets, one with 2426 hours soaking at 25ºC (77ºF) and another with vacuum saturation were used in the evaluation. Further, 20 drilled cores of 100mm diameter and approximately 12 150 mm height were vacuum saturated and subsequently used for the analysis. Each set were fed in to the CoreDryTM for drying. Drying time and drying efficiency were evaluated based on the previously determined dry weight from AASHTO T166. The result of this study in second attempt of drying with CoreDryTM for 24 hour soaked samples, removed 0.002 to 0.032 percent of water which is well below the 0.05 percent threshold value used in ovendrying constant mass definition. For the vacuum saturated specimens, the dry mass obtained after CoreDryTM showed that the degree of drying was less than the 0.2 % of the original dry mass and the difference in dry mass ranged from 0.043 to 0.211 percent of dry mass. The increased percentage of difference in dry mass was higher for the higher saturation. CoreDryTM produces the same results, but with the increased drying time and number of attempts for the vacuum saturated specimens. This study concluded with the following remarks (5): i) The CoreDryTM vacuum drying system consistently provides a reasonable estimate of constant mass in its initial attempt. ii) The CoreDryTM vacuum drying system provides reasonable estimates of constant mass for specimens with degree of saturation ranging up to ‘fully saturated’. Neal Retzer (7) conducted a review of InstroTek®’s CoreDryTM apparatus in 2005. The research objective was to evaluate if the CoreDryTM compares well enough with the conventional oven dry method. Both 100 mm and 150 mm diameter field cut cores were used in the analysis. Cores were first tested in CoreDryTM and tested in rapid oven drying at 110±5ºC (AASHTO T166, Method C) for dry mass. This study reported that the average difference in density came out to be 0.17 % and never exceeded 0.6 %. 13 Similarly, the difference in bulk specific gravity difference averaged 0.004 and never exceeded 0.016. CoreDryTM removed 86.9 % of the water while oven drying removed 91.2 % after drying in CoreDryTM. This shows the rapid drying is more effective than CoreDryTM drying method. The results seem to be bias as oven drying is followed by CoreDryTM for all of the samples. To overcome the bias results, 12 more samples with 90 seconds vacuum saturation were tested. This time comparison of weight of the sample before saturation, after saturation, after drying with CoreDryTM and oven drying were made. The average efficiency of CoreDryTM in removing water from the vacuum saturated samples was found to be 86.9% where as the average efficiency was found to be 91.2 % for oven drying. Based on efficiency in removing the water from the samples, the final conclusion was made in favor of CoreDryTM apparatus and can be accepted as an alternative to oven drying method (7). CoreReaderTM In July 2006, Stacy G. Williams (7) evaluated the bulk specific gravity obtained from CoreReaderTM. The comparison was done among the specific gravities obtained by AASHTO T166, CoreLokTM, CoreReaderTM and HeightDiameter procedure. The study was carried out using two different aggregate sizes and three different levels of compaction to account the effect of aggregate size and compactive effort on Gmb. All together, 72 samples were used in this study. A two way ANOVA with Duncan’s ranking indicated the AASHTO T166 method being most repeatable and consistent where as CoreReaderTM was statistically different, and seemed to be more variable. Individually, minimum variability was found in AASHTO T166 method (coefficient of variance 0.317) where as maximum variability in case of CoreReaderTM method (coefficient of variance 14 2.200). The CoreReaderTM Gmb was found to be statistically different than the AASHTO T166 and other methods. The study has also indicated that the variability in measured Gmb using CoreReaderTM is more for mixes with larger aggregate size (NMAS 25.0 mm and 37.5 mm). In this study, some samples were with heights which were out of range required for CoreReaderTM Gmb testing and alternative proportional height calculation was utilized (8). In another independent study by the Highway Materials Lab at North Carolina State University, (9) data were collected on 108 different specimens. Among the data collected were repeated specific gravity measurements with the CoreReaderTM at different measurement intervals. The average standard deviation of all 108 specimens comparing 4minute and 8minute counts was 0.0018. The test results also indicated that the CoreReaderTM is more precise than other methods currently used because of the increased sensitivity to the volumetric differences. SUMMARY After the review of the available literature, CoreDryTM apparatus seems promising in drying the lab compacted as well as field core samples for Gmb determination. The Gmb determined using CoreReaderTM apparatus seems different than AASHTO T166. Gmb from CoreReaderTM apparatus is expected to be less repeatable than AASHTO T166. 15 CHAPTER 3 TEST PLAN MATERIALS Lab Samples Two types of samples were evaluated, lab compacted and field cores. For the lab compacted samples, three types of mixes were used, an ODOT S3 mix, an ODOT S4 mix and an ODOT stone matrix asphalt (SMA) mix . The S3 and S4 mixes were prepared in the OSU bituminous laboratory. The SMA samples were obtained from a contractor’s lab. For the lab compacted S3 and S4 mixes, two different sample heights, 95±5 mm and 115±5 mm were prepared. The 95±5 mm and 115±5 mm high specimens were compacted at 7±0.5% and 4±0.5% VTM. Table 3.1 shows the heights and VTMs of the S3 and S4 mixes prepared in the laboratory. Table 3.1. Test Specimens of S3 and S4 Mix Mix Sample Height (mm) Diameter (mm) VTM (%) 95±5 150 7±0.5 S3 115±5 150 4±0.5 95±5 150 7±0.5 S4 115±5 150 4±0.5 Determination of bulk specific gravity (Gmb) of lab compacted samples is important for different laboratory distress evaluation tests. Distresses are directly related to pavement 16 performance. Moisture Induced Damage Test (AASHTO T283), Hamburg Wheel Track Testing (AASHTO T324) etc are used to evaluate pavement performance. These tests need samples with specific volumetric properties, which are ultimately based on Gmb of test specimens. The laboratory compacted 95±5mm high, 7±0.5% VTM samples were used to simulate AASHTO T283 test specimens and the 115±5mm high, and 4±0.5% VTM samples were selected to simulate the AASHTO T324 test specimens. S3 and S4 Mixes ODOT S3 and S4 mixes are fine graded mixes with nominal maximum aggregate size (NMAS) of 19.0 mm (3/4 inches) and 12.5 mm (1/2 inches), respectively. The S3 and S4 mixture were made with PG 6422 asphalt. The gradation of aggregate used in preparation of test specimens and ODOT mix specifications are presented in table 3.2. The grain size distribution curve of aggregates used for S3 and S4 mixes are presented in figure 3.1. TABLE 3.2. S3 and S4 Mix Design % Passing ODOT Specification Sieve Size S3 S4 S3 S4 1" 100 100 100 3/4" 100 100 90100 100 1/2" 85 94 <90 90100 3/8" 69 89 <90 No.4 47 62 No.8 32 40 3149 3458 No.16 23 28 No.30 19 20 No.50 8 12 No.100 5 7 No.200 4 5.2 28 210 Pb (%) 4.1 4.95 4.1 min. 4.6 min 17 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 Sieve Size (mm 0.45 ) % Passing . S3 S4 FIGURE 3.1 Grain size distribution curve of aggregate for S3 and S4 mixes. Stone Matrix Asphalt (SMA) Mix Stone Matrix Asphalt (SMA) is a special type of mix consisting of coarse aggregate with fines as mineral filler. It relies on stone onstone contact to provide strength. Generally, gapgraded aggregates are used to produce such a mix. The percentage of asphalt in an SMA mix is generally higher than a regular mix. The SMA specimens were obtained from a contractor’s lab, and the physical properties were not determined. A typical aggregate gradation for an SMA mix is shown in table 3.3 and typical grain size distribution curve in figure 3.2. 18 TABLE 3.3. Typical Gradation of Aggregate for SMA Sieve Size % passing 3/4" 100 1/2" 9097 3/8" 6085 No.4 2535 No.8 1525 No.200 812 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Sieve Size (mm 0.45 ) % Passing . SMA FIGURE 3.2 Typical grain size distribution curve for SMA mix. Field Cores Field cores of HMA were provided from various projects by a testing lab. There were two different sizes of cores provided, approximately 100 mm (4 inches) diameter and approximately 150mm (6 inches) diameter. All the cores upon arrival were numbered 19 with a sample marker and sorted into two sets. One set consisted of cores having both ends smooth and parallel and the other consisted of cores with one or both edges irregular. The set with both ends smooth were tested directly whereas the other set, with one or both the faces irregular, were first tested for CoreReaderTM Gmb using the average height and retested after being sawed to make the edges smooth and parallel. TEST PROCEDURES Lab Samples Two different sets of samples were prepared in the laboratory, one with 95±5 mm height of 7±0.5 % VTM to match the test specimens used for AASHTO T283 test and other set of specimens with 115±5 mm height of 4±0.5 % air void content to match the superpave mix design void requirements. Samples were compacted according to AASHTO T312. After compacting the samples, they were allowed to cool at room temperature overnight. After cooling to room temperature, the height of each sample was recorded at six evenly spaced locations using a digital caliper having precision of ±0.1mm. The average of six readings was reported as the height of the specimen. Samples were next tested in the CoreReaderTM apparatus using the measured height and reported as CoreReaderTM bulk specific gravity. After the CoreReaderTM Gmb measurement, the dry (initial dry), submerged and saturated surface dry (SSD) masses were obtained in accordance with AASHTO T166. The bulk specific gravity was calculated using the formula given below, The Gmb obtained using the initial dry mass is reported as T166 Gmb. The percent absorption of each sample was also calculated using the formula 20 If the percent absorption was above 2 %, the Gmb was determined using the CoreLokTM apparatus in accordance with AASHTO TP69 (ASTM D6752), and the bulk specific gravity obtained was reported as AASHTO T166 Gmb. For further testing, each set of 95mm and 115mm high samples of S3, S4 and SMA mixes were divided in to two groups, namely group A and B, and tested in two different sequences. Group A: After determining the SSD mass, samples were placed in an oven at 52±3ºC (125±5ºF) overnight. After oven drying overnight, the mass was measured at 2 hour intervals until the difference in mass was less than 0.05 %. This was reported as the slow oven dry mass of the sample. The bulk specific gravity calculated using equation 3.1 using the slow oven dry mass, and previously measured submerged and SSD mass in accordance with AASHTO T166, was reported as slow oven Gmb. When the slow oven drying was completed, the same sample was dried in the CoreDryTM apparatus (CoreDryTM mass). Finally, the sample was placed in an oven at 110±5ºC (230±9ºF) and the mass checked every 2 hours until the sample reached a constant mass, which is a mass loss of less than 0.05 % in a two hour period. The bulk specific gravity obtained at 110±5ºC is recorded as fast oven Gmb. Group B A second set of samples of equal number were tested in a similar method as group A. The only difference being the order of testing between the CoreDryTM and slow oven procedures. The initial dry, submerged and SSD masses were obtained and the Gmb 21 obtained based on initial dry mass is reported as T166 Gmb. After T166 Gmb, the same samples were dried in the CoreDryTM to get the CoreDryTM Gmb. Finally samples were processed for slow oven and then fast oven drying and reported as slow oven and fast oven Gmb. The sequence of testing for group A and group B lab samples is illustrated in the flow chart shown in figure 3.3. FIGURE 3.3 Test procedures for lab compacted sample. Field Cores The field cores had varying heights and diameters of either approximately 100 mm (4 inches) or approximately 150 mm (6 inches). The actual diameter for the small size cores ranged from 95.3 mm (3.75 inches) to 97.0 mm (3.82 inches) and the diameter Fast oven drying (Fast oven dry mass) Submerged mass Slow Oven drying (Slow oven dry mass) SSD mass Core drying (CoreDryTM mass) Lab sample CoreReaderTM Gmb measurement Height measurement Initial dry mass Core drying (CoreDryTM mass) Slow Oven drying (Slow oven dry mass) Group A Group B 22 of large size cores range from 143.6 mm (5.65 inches) to 154.0 mm (6.06 inches). The specified diameter of samples for the CoreReaderTM is either exactly 100 mm (4 inches) or exactly 150 mm (6 inches). Cores were assumed as 100 mm for all small size cores and 150 mm for all large size cores. Cores cannot be considered dry as lab compacted samples. Therefore, the cores were placed in the CoreDryTM apparatus prior to testing to reach the dry condition. After drying using the CoreDryTM, heights were measured and then testing followed. The CoreReaderTM testing, submerged mass, SSD mass, slow oven drying mass and fast oven drying mass were determined in the same group A and group B sequence as followed for laboratory prepared samples. Effect of Parallel Faces Before Sawing One of the objectives of this study was to determine the effect of end treatment on CoreReaderTM Gmb. For cores with one or both ends uneven, they were first dried in CoreDryTM and height was measured using a dial gauge at 12 different locations. The cores were then tested in CoreReaderTM using the average height obtained from dial gauge measurement. The Gmb so obtained is reported as CoreReaderTM Gmb before sawing. After Sawing The same cores tested above were then sawed to make the faces parallel and smooth. During the sawing care was taken to minimize the reduction in height. After sawing the cores, heights at six different locations were obtained with a digital caliper. The Gmb so obtained is reported is CoreReaderTM Gmb after sawing. These cores were 23 then placed in to regular testing described in phase II. The sequence of testing for group A and group B field cores is illustrated in the flow chart shown in figure 3.4. FIGURE 3.4 Test procedures for field core samples. Fast oven drying (Fast oven dry mass) Submerged mass Slow Oven drying (Slow oven dry mass) SSD mass Core drying (CoreDryTM mass) Field Cores Both ends smooth and Parallel? Height measurement Core drying (CoreDryTM mass) Yes Core drying (CoreDryTM mass) Slow Oven drying (Slow oven dry mass) CoreReaderTM Gmb measurement (before sawing) Sawing of cores No Method A Method B CoreReaderTM Gmb (after sawing) 24 ANALYSIS The main objectives of this study were to determine the drying efficiency of CoreDryTM and to evaluate the CoreReaderTM apparatus in determining the bulk specific gravity (Gmb) of asphalt paving mixtures. To meet the objectives, ANOVA with Duncan’s multiple range tests along with paired ttesting were used. Practical significance of any statistically different results was also taken into account while analyzing the test results. A correlation will be developed by regression analysis if the test results are found statistically as well as practically different. Phase I CoreDryTM In this phase the dry mass of field cores and lab compacted samples obtained using the CoreDryTM apparatus were compared with the dry mass obtained by slow oven and fast oven drying. For lab samples, one extra dry mass measurement was obtained, dry mass after cooling to room temperature, and was used in the analysis. Phase II CoreReaderTM This phase of the project concentrated on evaluation of Gmb obtained from the CoreReaderTM to that obtained from conventional water displacement method (AASHTO T166). The Gmb obtained after drying by CoreDryTM, slow oven and fast oven operation were used in this analysis phase. Phase III This phase of analysis consists of evaluation of effect of sample height and parallel faces on CoreReaderTM Gmb. This was accomplished by comparing the CoreReaderTM Gmb before sawing and CoreReaderTM Gmb after sawing. Paired ttest and ttest assuming equal variances were used in this analysis. 25 CHAPTER 4 TEST RESULTS The determination of bulk specific gravity of asphalt paving mixture was divided into two major parts, one using the CoreReaderTM apparatus and another using the AASHTO T166 procedure. Four different drying techniques were used in the AASHTO T166 procedure. The drying method used in AASHTO T166 includes: i) Drying the sample at room temperature for 24 hours (only applicable to lab compacted samples) ii) Drying using CoreDryTM apparatus iii) Drying at 52±3ºC (125±5ºF) for constant mass (Slow oven drying method) iv) Drying at 110±5ºC (230±9ºF) for constant mass (Fast oven or rapid drying method) Laboratory compacted ODOT S3, S4 and SMA mixes and field cores obtained from a contractor’s lab were used for testing. PHASE I COREDRYTM In this phase, lab compacted samples and field cores were tested for dry mass. For the lab compacted specimens, dry mass after cooling to room temperature (initial dry 26 mass), submerged and SSD mass and dry mass after slow oven and fast oven drying were obtained in accordance with AASHTO T166 and reported as initial dry mass, sub mass, SSD mass, slow oven dry mass and fast oven dry mass, respectively. In addition, dry mass of test specimens were obtained after drying in CoreDryTM and reported as CoreDryTM mass. In this phase, 59 laboratory compacted samples and 219 field cores were used. To prevent bias, the samples were divided into two sets for testing, group A and group B. Group A The lab compacted samples and field cores were tested for dry mass according to the following sequence of tests of group A samples: (i) CoreReaderTM Gmb, (ii) measurement of dry mass after cooling to room temperature (for lab compacted samples only), (iii) measurement of submerged mass, (iv) measurement of SSD mass, (v) measurement of dry mass after slow oven drying, (vi) measurement of dry mass after drying in CoreDryTM apparatus, and (vii) measurement of dry mass after fast oven drying. A total of 30 lab compacted samples and 103 field cores were tested. The test results for lab samples and field cores are presented in Table 4.1 and 4.2, respectively. Group B For this group, the lab compacted and field cores were tested for dry mass according to the following sequence: (i) CoreReaderTM Gmb, (ii) measurement of dry mass after cooling to room temperature (for lab compacted samples only), (iii) measurement of submerged mass, (iv) measurement of SSD mass, (v) measurement of dry mass after drying in CoreDryTM apparatus(vi) measurement of dry mass after slow oven drying, and (vii) measurement of dry mass after fast oven drying. A total of 29 lab 27 compacted samples and 116 field cores were tested. The test results for lab samples and field cores are presented in Tables 4.3 and 4.4, respectively. PHASE II COREREADERTM This phase of the project is the evaluation of Gmb obtained using the CoreReaderTM. The dry masses for lab compacted samples and field cores used in phase I were used in Gmb calculations for phase II. Therefore, the group A and B samples were the same as in phase I. All together, 59 laboratory compacted samples and 219 field cores were used in this phase, out of which 30 lab compacted samples and 103 field cores were tested in group A and 29 lab samples and 116 field cores were tested in group B. The results include the Gmb obtained after initial drying (T166 Gmb), slow oven drying (Slow oven Gmb), Fast oven drying (Fast oven Gmb), Gmb after drying in CoreDryTM (CoreDryTM Gmb) and Gmb obtained from CoreReaderTM apparatus (CoreReaderTM Gmb). The test results for lab samples and field cores for group A are presented in tables 4.5 and 4.6, respectively. Similarly, test results for group B lab samples and field cores are presented in tables 4.7 and 4.8, respectively. PHASE III This phase is the evaluation of the effect of height and parallel faces on CoreReaderTM Gmb. This section of test results consists of field cores only. The CoreReaderTM Gmb before sawing (CRD Gmb, before sawing) and CoreReaderTM Gmb after sawing (CRD Gmb, after sawing) were obtained according to test procedures for 28 field cores. A total of 94 field cores were tested. The test results are presented in table 4.9. TABLE 4.1. Lab Test Result of Lab Compacted Samples, Phase I, Group A Sample ID Mix Initial dry mass (g) Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) 95 (1) S3 3883.3 2283.3 3910.7 3886.7 3883.8 3883.2 95 (6) S3 3873.0 2272.5 3905.4 3874.1 3874.0 3874.0 95 (7) S3 3871.3 2275.9 3900.2 3871.3 3870.8 3870.8 95 (8) S3 3877.5 2277.2 3906.2 3879.1 3878.2 3877.8 115 (3) S3 4927.2 2943.5 4939.0 4927.5 4927.2 4923.6 115 (4) S3 4912.6 2936.1 4928.2 4914.6 4913.3 4910.4 115 (5) S3 4919.5 2934.9 4930.6 4920.6 4919.8 4916.5 115 (7) S3 4913.2 2935.1 4924.2 4913.7 4913.7 4913.7 115 (8) S3 4902.1 2928.7 4917.7 4902.6 4902.2 4902.2 95(2) S4 3591.3 2026.7 3615.0 3596.0 3593.2 3592.3 95(3) S4 3603.7 2033.8 3627.9 3609.0 3605.7 3604.9 95(4) S4 3595.6 2028.2 3620.0 3601.0 3597.7 3596.7 95(5) S4 3602.1 2033.1 3623.9 3605.9 3603.7 3603.0 115(1) S4 4515.0 2581.2 4520.9 4515.2 4515.1 4515.0 115(2) S4 4504.7 2578.1 4510.8 4504.8 4504.8 4504.7 115(3) S4 4502.1 2572.0 4508.9 4502.4 4502.3 4502.1 115(4) S4 4505.9 2577.4 4511.5 4506.1 4506.1 4506.0 S(1) SMA 4755.7 2771.1 4759.7 4755.9 4755.9 4755.7 S(2) SMA 4768.8 2719.3 4783.5 4770.1 4769.0 4768.6 S(3) SMA 4762.0 2744.9 4767.9 4762.3 4762.2 4762.0 S(4) SMA 4780.9 2730.8 4792.5 4781.5 4781.1 4780.8 S(5) SMA 4767.5 2755.5 4772.0 4767.8 4767.7 4767.6 S(6) SMA 4765.2 2713.3 4784.0 4767.2 4765.5 4765.0 S(7) SMA 4761.1 2717.7 4771.5 4762.3 4761.1 4760.8 S(8) SMA 4776.3 2717.1 4789.7 4777.9 4776.5 4776.2 S(9) SMA 4769.0 2770.5 4775.6 4769.4 4769.2 4769.0 S(10) SMA 4763.1 2738.7 4767.5 4763.4 4763.3 4763.1 S(11) SMA 4763.2 2736.2 4768.7 4763.3 4763.3 4763.2 S(12) SMA 4772.7 2721.0 4781.8 4773.5 4772.9 4772.7 S(13) SMA 4752.4 2766.7 4757.9 4752.6 4752.5 4752.3 29 TABLE 4.2. Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) A1 820.8 1493.2 1482.9 1482.9 1481.4 A2 745.7 1338.2 1330.9 1330.9 1329.8 A3 828.2 1512.6 1500.0 1500.0 1498.2 A4 617.0 1120.0 1108.1 1108.1 1107.1 A5 677.3 1228.9 1215.5 1215.5 1214.5 A6 682.1 1235.5 1226.3 1226.3 1224.1 A7 807.8 1448.2 1444.4 1444.4 1443.8 A8 747.3 1357.2 1346.5 1346.5 1345.2 A9 613.3 1120.9 1112.6 1112.6 1111.5 B1 265.8 478.7 476.5 476.4 476.1 B2 267.4 480.3 478.4 478.4 478.2 B3 384.7 701.9 691.7 691.1 689.7 B4 387.5 704.2 694.7 694.4 693.5 B5 441.9 800.2 796.6 796.5 796.2 B6 589.5 1078.8 1071.9 1071.5 1071.0 B7 662.5 1196.1 1192.2 1191.6 1191.1 B8 624.3 1133.7 1128.7 1128.7 1127.9 B9 642.0 1161.0 1156.5 1156.1 1155.3 B10 587.0 1075.7 1069.2 1068.4 1067.7 B11 683.0 1237.4 1231.9 1231.5 1230.9 T115 890.9 1551.7 1550.5 1550.5 1550.2 T116 969.3 1712.2 1709.3 1709.2 1708.4 T117 735.3 1286.1 1283.9 1283.8 1283.3 T118 833.7 1502.2 1480.6 1481.3 1480.3 T119 961.0 1688.9 1685.5 1685.4 1685.1 T120 2371.3 4085.1 4072.3 4071.1 4069.7 T121 646.7 1161.2 1148.8 1147.3 1145.8 T122 882.4 1552.1 1549.0 1549.0 1548.7 T123 713.5 1249.0 1247.4 1247.5 1247.2 T124 685.0 1204.4 1202.6 1202.6 1202.3 T125 1000.5 1779.6 1772.5 1772.2 1771.2 T126 662.3 1172.1 1172.1 1170.9 1169.9 T127 862.7 1535.9 1529.4 1529.3 1528.5 T21 731.8 1278.8 1277.2 1277.1 1277.1 T22 723.9 1281.6 1277.8 1277.7 1277.7 30 TABLE 4.2. (Con’t.) Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) T23 864.3 1531.2 1528.6 1528.4 1528.4 T24 795.0 1403.3 1399.7 1399.7 1399.6 T25 941.6 1672.7 1665.5 1664.7 1663.6 T26 783.4 1430.5 1404.9 1399.9 1393.6 T27 1000.8 1730.0 1728.8 1728.7 1728.7 T28 903.1 1581.6 1578.9 1578.8 1578.5 T29 896.7 1582.3 1578.1 1578.0 1577.8 T210 1454.3 2569.9 2563.5 2563.1 2562.1 T211 814.2 1435.5 1432.1 1432.1 1431.9 T212 798.8 1409.3 1405.6 1405.6 1405.4 T213 1033.4 1787.1 1785.5 1785.5 1785.5 T214 996.7 1739.6 1738.3 1738.3 1738.1 T215 1281.6 2235.8 2232.2 2232.2 2231.6 T216 788.4 1379.9 1378.3 1378.3 1378.2 T217 741.5 1310.8 1307.9 1307.9 1307.8 T218 861.8 1496.9 1495.7 1495.7 1495.6 T219 869.8 1550.5 1541.9 1541.9 1541.2 T220 1001.5 1745.9 1742.3 1742.3 1742.0 T221 717.4 1261.2 1259.2 1259.2 1259.2 T222 772.7 1374.7 1371.5 1371.5 1371.2 T223 892.4 1544.9 1544.0 1544.0 1543.9 T224 1354.6 2398.2 2386.2 2386.2 2385.3 SC1 1122.0 1957.7 1954.8 1954.8 1954.7 SC2 1311.5 2289.9 2286.6 2286.6 2286.5 SC3 1231.1 2177.5 2171.9 2171.5 2171.4 SC4 1129.7 1975.1 1971.1 1971.6 1971.5 SC5 1045.8 1839.7 1835.6 1835.5 1835.3 B32 932.3 1669.9 1664.7 1664.5 1663.9 B33 832.2 1504.6 1496.9 1496.4 1494.6 B34 857.7 1523.9 1520.8 1520.8 1520.5 B35 1180.2 2111.5 2105.3 2104.7 2104.1 B36 1006.1 1803.9 1798.0 1797.9 1797.4 B37 570.7 1040.5 1033.5 1032.7 1032.4 B38 879.9 1557.8 1554.4 1554.4 1554.1 B39 536.4 970.8 966.9 966.7 966.6 T136 981.8 1740.0 1734.1 1734.1 1733.6 31 TABLE 4.2. (Con’t.) Lab Test Results of Field Cores, Phase I, Group A Sample ID Sub. mass (g) SSD mass (g) Slow oven dry mass (g) CoreDryTM dry mass (g) Fast oven dry mass (g) T137 1572.6 2721.0 2715.3 2714.4 2713.6 T138 1759.7 3034.8 3032.1 3032.1 3031.7 T139 1520.5 2616.0 2613.2 2613.1 2612.8 T140 2167.9 3787.2 3770.9 3765.7 3762.8 T141 2217.6 3815.5 3808.9 3808.1 3807.1 T142 1692.6 2903.8 2900.5 2900.5 2900.0 T143 1961.5 3373.5 3368.4 3368.0 3366.9 T144 1418.9 2459.0 2453.4 2453.3 2452.9 T271 1780.7 3070.9 3061.4 3061.2 3060.6 T272 1257.9 2227.4 2207.2 2207.1 2204.6 T273 970.4 1765.4 1751.6 1750.8 1749.0 T274 1799.6 3290.0 3264.1 3257.2 3256.9 T275 1512.4 2608.7 2604.5 2604.5 2604.0 T276 1479.3 2608.5 2604 2603.5 2603.1 T277 1756.2 3025.2 3019 3017.8 3015.0 T278 1441.1 2499.0 2491.8 2491.0 2490.2 T279 1416.6 2437.5 2435.2 2435.3 2435.1 T280 1469.7 2547.1 2532.9 2530.4 2529.2 T281 1483.7 2696.0 2674.1 2670.2 2666.9 T282 1333.7 2338.8 2330.7 2329.6 2328.6 T283 1060.9 1908.8 1900.9 1900.9 1899.3 T284 946.8 1632.9 1630.3 1630.3 1629.9 T285 2318.5 4129.3 4120.8 4120.7 4119.1 T286 2291.8 4021.0 4016.4 4016.2 4014.7 T287 1830.9 3152.8 3144.1 3142.9 3141.7 T288 967.3 1742.6 1739.8 1739.8 1739.6 T289 1149.6 1987.5 1983.7 1983.7 1983.2 T290 1284.9 2249.7 2247.4 2247.0 2246.5 T291 1114.8 1939.9 1933.8 1933.1 1932.4 T292 2311.5 4015.4 3999.6 3995.4 3994.1 T293 2126.0 3740.0 3732.8 3731.1 3728.7 32 TABLE 4.3. Lab Test Results of Lab Compacted Samples, Phase I, Group B Sample ID Mix Initial dry mass (g) Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) 95 (10) S3 3857.3 2262.1 3888.3 3858.3 3857.4 3857.2 95(11) S3 3887.2 2280.0 3914.6 3887.8 3887.3 3887.3 95(12) S3 3862.8 2261.1 3893.0 3863.1 3862.9 3862.8 95(13) S3 3879.0 2279.0 3907.2 3879.8 3878.1 3878.1 115(9) S3 4928.6 2942.5 4938.7 4928.7 4928.6 4928.5 115(10) S3 4907.3 2935.6 4919.1 4907.8 4907.3 4907.2 115 (11) S3 4921.8 2941.7 4930.8 4922.2 4921.8 4921.5 115(12) S3 4912.9 2926.7 4920.1 4913.1 4913.0 4913 115(13) S3 4921.6 2940.4 4931.4 4921.7 4921.6 4921.6 95(6) S4 3596.7 2029.5 3618.5 3597.2 3596.8 3596.7 95(8) S4 3607.4 2036.9 3627.9 3608.1 3607.5 3607.4 95(9) S4 3594.2 2029.3 3620.6 3594.9 3594.2 3594.1 95(10) S4 3605.1 2036.1 3626.4 3606.0 3605.2 3605.1 115(5) S4 4505.3 2583.4 4513.9 4505.7 4505.5 4505.3 115(6) S4 4521.4 2591.3 4529.0 4521.4 4521.4 4521.4 115(7) S4 4510.1 2581.9 4519.2 4510.2 4510.2 4510.1 115(8) S4 4518.3 2587.3 4524.6 4518.3 4518.3 4518.3 S(14) SMA 4768.8 2714.9 4786.9 4769.2 4768.5 4768.2 S(15) SMA 4764.9 2780.0 4769.2 4764.9 4764.7 4764.5 S(16) SMA 4774.1 2749.0 4784.4 4774.3 4773.9 4773.6 S(17) SMA 4762.7 2778.3 4767.3 4762.7 4762.5 4762.2 S(18) SMA 4772.0 2739.9 4780.6 4772.2 4771.8 4771.6 S(19) SMA 4773.7 2778.6 4779.8 4773.7 4773.3 4773.1 S(20) SMA 4765.0 2774.2 4769.0 4765.1 4764.8 4764.5 S(21) SMA 4766.1 2773.7 4771.8 4766.1 4765.8 4765.5 S(22) SMA 4773.0 2776.6 4779.9 4773 4772.7 4772.4 S(23) SMA 4765.4 2744.9 4770.8 4765.4 4765.2 4764.9 S(24) SMA 4777.3 2749.7 4787.1 4777.4 4777.0 4776.6 S(25) SMA 4766.7 2772.3 4772.6 4766.7 4766.4 4766.2 33 TABLE 4.4. Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) A10 689.4 1240.5 1234.3 1233.6 1232.9 A11 730.6 1326.7 1316.7 1316.0 1315.4 B12 1006.0 1791.2 1791.2 1790.3 1789.9 B13 1003.3 1788.8 1788.8 1787.7 1787.4 B14 444.5 802.8 802.8 802.2 802.0 B15 385.7 698.2 698.2 697.5 696.9 B16 636.4 1149.8 1145.1 1144.4 1143.7 B17 571.8 1021.0 1021.0 1020.4 1020.1 B18 714.8 1287.3 1287.3 1286.6 1286.4 B19 625.9 1136.2 1136.2 1135.6 1135.4 B20 684.4 1247.8 1247.8 1246.9 1246.6 B21 633.8 1137.9 1137.9 1137.2 1136.8 B22 570.4 1049.1 1049.1 1048.4 1048.2 T11 687.9 1207.0 1204.6 1204.0 1203.7 T12 925.9 1638.9 1632.3 1631.8 1631.4 T13 929.2 1632.0 1629.3 1628.7 1628.3 T14 835.0 1501.9 1486.6 1485.4 1484.7 T15 919.6 1602.4 1601.3 1600.9 1600.8 T16 804.8 1422.0 1418.9 1417.7 1417.4 T17 775.2 1377.9 1373.3 1372.6 1372.0 T18 879.0 1555.0 1552.6 1552.1 1551.8 T19 807.4 1406.1 1404.9 1404.7 1704.6 T110 2059.1 3533.6 3528.9 3527.6 3527.3 T111 1775.2 3060.9 3052.7 3051.8 3051.7 T112 1805.2 3128.8 3123.1 3122.4 3122.1 T113 846.5 1489.0 1487.5 1487.3 1487.0 T114 910.9 1587.3 1586.3 1586.1 1585.9 T225 772.2 1351.9 1350.7 1350.3 1350.2 T226 846.2 1497.2 1494.4 1493.9 1493.8 T227 909.4 1573.3 1571.8 1571.4 1571.3 T228 772.1 1353.6 1351.6 1351.2 1351.0 T229 792.4 1386.7 1384.7 1384.4 1384.2 T230 741.7 1316.2 1310.0 1308.8 1308.5 T231 799.1 1409.4 1406.9 1406.4 1406.2 T232 833.7 1449.9 1448.1 1447.8 1447.6 T233 902.2 1588.1 1585.3 1584.7 1584.4 34 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) T234 979.7 1715.2 1713.0 1712.4 1712.1 T235 853.4 1497.8 1495.8 1495.2 1495.1 T236 824.1 1464.8 1456.7 1455.2 1454.8 T237 897.0 1565.8 1562.6 1562.0 1561.7 T238 896.9 1584.5 1579.6 1578.9 1578.5 T239 864.5 1513.6 1511.1 1510.6 1510.4 T240 985.3 1728.8 1727.2 1726.9 1726.9 T241 889.7 1563.3 1561.3 1560.9 1560.8 T242 890.8 1554.1 1552.4 1552.1 1552.0 T243 929.3 1618.5 1617.2 1617.0 1617.0 T244 991.9 1753.9 1750.0 1749.3 1749.1 T245 935.1 1625.0 1623.4 1623.1 1623.0 T246 893.9 1553.4 1552.0 1551.7 1551.7 T247 779.5 1368.8 1367.0 1366.8 1366.7 T286 1508.1 2640.3 2634.5 2633.7 2633.5 T213B 929.0 1622.0 1620.1 1619.9 1619.9 SC6 1254.2 2196.1 2193.2 2192.9 2192.7 SC7 1375.8 2392.3 2388.9 2388.8 2388.7 SC8 1280.4 2263.9 2257.5 2257.1 2256.9 SC9 1294.9 2260.4 2256.5 2256.2 2256.1 H1 946.0 1724.0 1713.9 1712.8 1712.3 H2 720.3 1270.3 1269.0 1268.8 1268.7 H3 1764.0 3091.8 3085.5 3084.6 3084.3 H4 690.6 1208.4 1206.8 1206.6 1206.3 H5 1496.2 2606.2 2603.0 2602.2 2601.7 H6 1255.4 2231.0 2223.1 2221.8 2221.2 H7 1112.2 1915.4 1913.5 1913.1 1912.8 H8 1420.8 2454.6 2453.1 2452.8 2452.3 H9 1052.5 1808.9 1807.2 1806.9 1806.4 H10 899.9 1606.0 1603.2 1602.5 1601.9 H11 1223.8 2180.4 2168.2 2166.7 2166.0 H12 923.7 1611.0 1607.4 1606.7 1605.5 H13 1697.7 2962.8 2959.5 2958.8 2958.2 A12 781.8 1420.1 1409.1 1407.8 1407.3 A13 587.9 1055.2 1049.7 1048.8 1048.5 35 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) A14 777.2 1416.3 1406.2 1404.6 1403.7 A15 637.9 1149.1 1141.3 1140.1 1139.4 A16 690.5 1246.7 1241.5 1240.3 1239.9 A17 554.6 1002.6 999.0 998.2 997.6 A18 556.3 1008.8 1000.8 999.7 999.2 B23 619.5 1121.1 1117.9 1117.0 1116.7 B24 621.2 1121.5 1118.9 1117.8 1117.7 B25 629.1 1153.1 1146.3 1145.0 1144.8 B26 331.9 602.0 599.4 598.8 598.6 B27 828.0 1503.1 1492.6 1490.7 1490.2 B28 953.0 1705.4 1701.4 1700.1 1699.7 B29 815.0 1446.6 1444.3 1443.4 1443.2 B30 1050.5 1882.9 1877.9 1876.4 1876.0 B31 527.3 954.3 949.7 948.3 947.8 T128 839.7 1491.3 1489.2 1488.4 1488.0 T129 1021.8 1768.1 1757.3 1754.1 1752.6 T130 1948.0 3369.9 3367.0 3360.0 3365.9 T131 1439.2 2481.2 2476.9 2475.7 2474.9 T132 1535.4 2671.2 2668.5 2667.5 2667.3 T133 923.2 1583.3 1581.9 1581.2 1580.7 T134 1418.3 2430.8 2428.1 2428.1 2427.1 T135 1803.2 3104.9 3102.6 3102.6 3101.2 T248 991.0 1831.0 1806.7 1799.5 1797.5 T249 761.5 1332.7 1330.6 1329.8 1329.5 T250 1751.8 3053.2 3046.0 3044.2 3043.5 T251 1647.4 2854.0 2844.7 2841.9 2841.2 T252 1683.2 2908.3 2904.3 2903.0 2902.4 T253 1436.9 2521.3 2515.7 2514.6 2514.0 T254 3192.9 5571.1 5532.0 5527.3 5525.0 T255A 916.3 1634.5 1631.7 1630.6 1630.2 T255B 1840.0 3168.7 3160.6 3157.3 3154.4 T256 1717.5 2982.7 2970.7 2969.1 2968.5 T257 2300.6 3987.3 3966.0 3962.0 3958.7 T258 1015.6 1873.1 1832.6 1827.3 1824.6 T259 3235.3 5595.3 5588.5 5586.2 5584.9 36 TABLE 4.4. (Con’t.) Lab Test Results of Field Cores, Phase I, Group B Sample ID Sub. mass (g) SSD mass (g) CoreDryTM dry mass (g) Slow oven dry mass (g) Fast oven dry mass (g) T260 2060.8 3554.6 3544.5 3542.1 3541.4 T261 977.1 1773.2 1765.7 1763.1 1761.6 T262 1570.4 2722.0 2718.9 2717.9 2717.6 T263 1145.8 1986.8 1983.2 1982.3 1982.1 T264 1666.4 2874.4 2870.5 2869.9 2869.8 T265 1543.9 2679.0 2671.7 2670.6 2670.4 T266 1415.7 2487.0 2442.4 2439.1 2438.2 T267 1699.1 2934.3 2929.3 2928.2 2928.1 T268 1070.4 1850.9 1846.1 1845.2 1845.0 T269 848.4 1531.3 1523.3 1519.5 1517.5 37 TABLE 4.5. Lab Test Results of Lab Compacted Samples, Phase II, Group A Sample ID Mix CoreReaderTM Gmb T166 Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb 95 (1) S3 2.339 2.386 2.388 2.387 2.386 95(6) S3 2.332 2.372 2.373 2.372 2.373 95(7) S3 2.324 2.383 2.383 2.383 2.383 95(8) S3 2.337 2.380 2.381 2.381 2.380 115(3) S3 2.437 2.469 2.469 2.469 2.467 115(4) S3 2.447 2.466 2.467 2.466 2.465 115(5) S3 2.460 2.465 2.466 2.465 2.464 115(7) S3 2.449 2.470 2.470 2.470 2.470 115(8) S3 2.447 2.465 2.465 2.465 2.465 95(2) S4 2.224 2.261 2.262 2.262 2.262 95(3) S4 2.227 2.261 2.262 2.262 2.261 95(4) S4 2.229 2.259 2.260 2.260 2.260 95(5) S4 2.222 2.264 2.265 2.265 2.265 115(1) S4 2.309 2.328 2.328 2.328 2.328 115(2) S4 2.305 2.331 2.331 2.331 2.331 115(3) S4 2.315 2.324 2.325 2.324 2.324 115(4) S4 2.319 2.330 2.330 2.330 2.330 S(1) SMA 2.367 2.391 2.392 2.392 2.391 S(2) SMA 2.279 2.310 2.311 2.310 2.310 S(3) SMA 2.295 2.354 2.354 2.354 2.354 S(4) SMA 2.278 2.319 2.319 2.319 2.319 S(5) SMA 2.313 2.364 2.364 2.364 2.364 S(6) SMA 2.247 2.301 2.302 2.301 2.301 S(7) SMA 2.275 2.318 2.319 2.318 2.318 S(8) SMA 2.253 2.304 2.305 2.305 2.304 S(9) SMA 2.351 2.378 2.379 2.379 2.378 S(10) SMA 2.301 2.348 2.348 2.348 2.348 S(11) SMA 2.281 2.344 2.344 2.344 2.344 S(12) SMA 2.265 2.316 2.316 2.316 2.316 S(13) SMA 2.358 2.387 2.387 2.387 2.387 38 TABLE 4.6. Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb A1 100 2.173 2.205 2.205 2.203 A2 100 2.214 2.246 2.246 2.244 A3 100 2.143 2.192 2.192 2.189 A4 100 2.154 2.203 2.203 2.201 A5 100 2.140 2.204 2.204 2.202 A6 100 2.187 2.216 2.216 2.212 A7 100 2.229 2.255 2.255 2.255 A8 100 2.167 2.208 2.208 2.206 A9 100 2.126 2.192 2.192 2.190 B1 100 2.194 2.238 2.238 2.236 B2 100 2.216 2.247 2.247 2.246 B3 100 2.118 2.181 2.179 2.174 B4 100 2.135 2.194 2.193 2.190 B5 100 2.166 2.223 2.223 2.222 B6 100 2.146 2.191 2.190 2.189 B7 100 2.191 2.234 2.233 2.232 B8 100 2.157 2.216 2.216 2.214 B9 100 2.204 2.228 2.228 2.226 B10 100 2.156 2.188 2.186 2.185 B11 100 2.190 2.222 2.221 2.220 T115 150 2.276 2.346 2.346 2.346 T116 150 2.228 2.301 2.301 2.300 T117 150 2.299 2.331 2.331 2.330 T118 150 2.144 2.215 2.216 2.214 T119 150 2.236 2.316 2.315 2.315 T120 150 2.339 2.376 2.375 2.375 T121 150 2.172 2.233 2.230 2.227 T122 150 2.246 2.313 2.313 2.313 T123 150 2.268 2.329 2.330 2.329 T124 150 2.253 2.315 2.315 2.315 T125 150 2.205 2.275 2.275 2.273 T126 150 2.179 2.299 2.297 2.295 T127 150 2.190 2.272 2.272 2.270 T21 150 2.307 2.335 2.335 2.335 T22 150 2.209 2.291 2.291 2.291 39 TABLE 4.6. (Con’t.) Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb T23 150 2.231 2.292 2.292 2.292 T24 150 2.237 2.301 2.301 2.301 T25 150 2.199 2.278 2.277 2.275 T26 150 2.076 2.171 2.163 2.154 T27 150 2.322 2.371 2.371 2.371 T28 150 2.265 2.327 2.327 2.326 T29 150 2.246 2.302 2.302 2.301 T210 150 2.223 2.298 2.298 2.297 T211 150 2.254 2.305 2.305 2.305 T212 150 2.226 2.302 2.302 2.302 T213 150 2.331 2.369 2.369 2.369 T214 150 2.284 2.340 2.340 2.340 T215 150 2.262 2.339 2.339 2.339 T216 150 2.264 2.330 2.330 2.330 T217 150 2.217 2.297 2.297 2.297 T218 150 2.300 2.355 2.355 2.355 T219 150 2.192 2.265 2.265 2.264 T220 150 2.262 2.341 2.341 2.340 T221 150 2.261 2.316 2.316 2.316 T222 150 2.217 2.278 2.278 2.278 T223 150 2.316 2.366 2.366 2.366 T224 150 2.220 2.287 2.287 2.286 SC1 150 2.251 2.339 2.339 2.339 SC2 150 2.263 2.337 2.337 2.337 SC3 150 2.197 2.295 2.294 2.294 SC4 150 2.230 2.332 2.332 2.332 SC5 150 2.203 2.312 2.312 2.312 B32 100 2.246 2.257 2.257 2.256 B33 100 2.204 2.226 2.225 2.223 B34 100 2.257 2.283 2.283 2.282 B35 100 2.245 2.261 2.260 2.259 B36 100 2.235 2.254 2.254 2.253 B37 100 2.177 2.200 2.198 2.198 B38 100 2.260 2.293 2.293 2.293 B39 100 2.202 2.226 2.225 2.225 40 TABLE 4.6. (Con’t.) Lab Test Results of Field Cores, Phase II, Group A Sample ID Diameter (mm) CoreReaderTM Gmb Slow oven Gmb CoreDryerTM Gmb Fast oven Gmb B40 100 2.235 2.261 2.260 2.260 T136 150 2.236 2.287 2.287 2.286 T137 150 2.312 2.364 2.364 2.363 T138 150 2.332 2.378 2.378 2.378 T139 150 2.343 2.385 2.385 2.385 T140 150 2.267 2.329 2.326 2.324 T141 150 2.352 2.384 2.383 2.383 T142 150 2.364 2.395 2.395 2.394 T143 150 2.352 2.386 2.385 2.384 T144 150 2.313 2.359 2.359 2.358 T271 150 2.343 2.373 2.373 2.372 T272 150 2.204 2.277 2.277 2.274 T273 150 2.160 2.203 2.202 2.200 T274 150 2.163 2.190 2.185 0.000 T275 150 2.340 2.376 2.376 2.375 T276 150 2.261 2.306 2.306 2.305 T277 150 2.359 2.379 2.378 2.376 T278 150 2.310 2.355 2.355 2.354 T279 150 2.348 2.385 2.385 2.385 T280 150 2.321 2.351 2.349 2.348 T281 150 2.152 2.206 2.203 2.200 T282 150 2.254 2.319 2.318 2.317 T283 150 2.228 2.242 2.242 2.240 T284 150 2.311 2.376 2.376 2.376 T285 150 2.253 2.276 2.276 2.275 T286 150 2.316 2.323 2.323 2.322 T287 150 2.348 2.378 2.378 2.377 T288 150 2.216 2.244 2.244 2.244 T289 150 2.341 2.367 2.367 2.367 T290 150 2.301 2.329 2.329 2.328 T291 150 2.290 2.344 2.343 2.342 T292 150 2.317 2.347 2.345 2.344 T293 150 2.300 2.313 2.312 2.310 41 TABLE 4.7. Lab Test Results of Lab Compacted Samples, Phase II, Group B Sample ID Mix CoreReaderTM Gmb T166 Gmb CoreDryTM Gmb Slow oven Gmb Fast oven Gmb 95(10) S3 2.312 2.372 2.373 2.372 2.372 95(11) S3 2.332 2.378 2.378 2.378 2.378 95(12) S3 2.311 2.367 2.367 2.367 2.367 95(13) S3 2.326 2.382 2.383 2.382 2.382 115 (9) S3 2.469 2.469 2.469 2.469 2.469 115(10) S3 2.439 2.474 2.474 2.474 2.474 115(11) S3 2.437 2.474 2.475 2.474 2.474 115(12) S3 2.458 2.465 2.465 2.465 2.465 115(13) S3 2.458 2.472 2.472 2.472 2.472 95(6) S4 2.231 2.263 2.264 2.264 2.263 95(8) S4 2.232 2.267 2.268 2.267 2.267 95(9) S4 2.217 2.259 2.259 2.259 2.259 95(10) S4 2.251 2.267 2.267 2.267 2.267 115(5) S4 2.303 2.334 2.334 2.334 2.334 115(6) S4 2.316 2.333 2.333 2.333 2.333 115(7) S4 2.314 2.328 2.328 2.328 2.328 115(8) S4 2.314 2.332 2.332 2.332 2.332 S(14) SMA 2.260 2.302 2.302 2.301 2.301 S(15) SMA 2.376 2.395 2.395 2.395 2.395 S(16) SMA 2.294 2.346 2.346 2.345 2.345 S(17) SMA 2.371 2.395 2.395 2.394 2.394 S(18) SMA 2.296 2.338 2.339 2.338 2.338 S(19) SMA 2.371 2.385 2.385 2.385 2.385 S(20) SMA 2.367 2.389 2.389 2.389 2.388 S(21) SMA 2.338 2.385 2.385 2.385 2.385 S(22) SMA 2.363 2.383 2.383 2.382 2.382 S(23) SMA 2.318 2.352 2.352 2.352 2.352 S(24) SMA 2.310 2.345 2.345 2.345 2.344 S(25) SMA 2.346 2.383 2.383 2.383 2.383 42 TABLE 4.8. Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb A10 100 2.191 2.240 2.238 2.237 A11 100 2.185 2.209 2.208 2.207 B12 100 2.261 2.281 2.280 2.280 B13 100 2.242 2.277 2.276 2.275 B14 100 2.186 2.241 2.239 2.238 B15 100 2.117 2.234 2.232 2.230 B16 100 2.182 2.230 2.229 2.228 B17 100 2.225 2.273 2.272 2.271 B18 100 2.193 2.249 2.247 2.247 B19 100 2.138 2.227 2.225 2.225 B20 100 2.148 2.215 2.213 2.213 B21 100 2.178 2.257 2.256 2.255 B22 100 2.066 2.192 2.190 2.190 T11 150 2.282 2.321 2.319 2.319 T12 150 2.213 2.289 2.289 2.288 T13 150 2.255 2.318 2.317 2.317 T14 150 2.154 2.229 2.227 2.226 T15 150 2.275 2.345 2.345 2.344 T16 150 2.225 2.299 2.297 2.297 T17 150 2.222 2.279 2.277 2.276 T18 150 2.260 2.297 2.296 2.296 T19 150 2.274 2.347 2.346 2.847 T110 150 2.358 2.393 2.392 2.392 T111 150 2.254 2.374 2.374 2.374 T112 150 2.305 2.360 2.359 2.359 T113 150 2.257 2.315 2.315 2.314 T114 150 2.279 2.345 2.345 2.345 T225 150 2.289 2.330 2.329 2.329 T226 150 2.222 2.296 2.295 2.295 T227 150 2.313 2.368 2.367 2.367 T228 150 2.278 2.324 2.324 2.323 T229 150 2.290 2.330 2.329 2.329 T230 150 2.189 2.280 2.278 2.278 T231 150 2.264 2.305 2.304 2.304 T232 150 2.285 2.350 2.350 2.349 T233 150 2.270 2.311 2.310 2.310 43 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb T234 150 2.286 2.329 2.328 2.328 T235 150 2.248 2.321 2.320 2.320 T236 150 2.214 2.274 2.271 2.271 T237 150 2.286 2.336 2.336 2.335 T238 150 2.228 2.297 2.296 2.296 T239 150 2.283 2.328 2.327 2.327 T240 150 2.272 2.323 2.323 2.323 T241 150 2.246 2.318 2.317 2.317 T242 150 2.295 2.340 2.340 2.340 T243 150 2.292 2.346 2.346 2.346 T244 150 2.223 2.297 2.296 2.295 T245 150 2.302 2.353 2.353 2.353 T246 150 2.303 2.353 2.353 2.353 T247 150 2.284 2.320 2.319 2.319 T286 150 2.265 2.327 2.326 2.326 T213B 150 2.290 2.338 2.338 2.338 SC6 150 2.249 2.328 2.328 2.328 SC7 150 2.270 2.350 2.350 2.350 SC8 150 2.196 2.295 2.295 2.295 SC9 150 2.244 2.337 2.337 2.337 H1 150 2.181 2.203 2.201 2.201 H2 150 2.276 2.307 2.307 2.307 H3 150 2.283 2.324 2.323 2.323 H4 150 2.339 2.331 2.330 2.330 H5 150 2.308 2.345 2.344 2.344 H6 150 2.26 2.279 2.277 2.277 H7 150 2.354 2.382 2.381 2.381 H8 150 2.353 2.373 2.372 2.372 H9 150 2.373 2.389 2.388 2.388 H10 150 2.244 2.270 2.270 2.269 H11 150 2.234 2.267 2.265 2.264 H12 150 2.320 2.339 2.338 2.336 H13 150 2.311 2.339 2.339 2.338 A12 100 2.195 2.195 2.206 2.205 A13 100 2.236 2.236 2.244 2.244 44 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb A14 100 2.183 2.183 2.198 2.196 A15 100 2.200 2.200 2.230 2.229 A16 100 2.208 2.208 2.230 2.229 A17 100 2.209 2.209 2.228 2.227 A18 100 2.171 2.171 2.209 2.208 B23 100 2.210 2.210 2.227 2.226 B24 100 2.218 2.218 2.234 2.234 B25 100 2.147 2.147 2.185 2.185 B26 100 2.178 2.178 2.217 2.216 B27 100 2.186 2.186 2.208 2.207 B28 100 2.232 2.232 2.260 2.259 B29 100 2.257 2.257 2.285 2.285 B30 100 2.244 2.244 2.254 2.254 B31 100 2.192 2.192 2.221 2.220 T128 150 2.250 2.285 2.284 2.284 T129 150 2.259 2.355 2.350 2.348 T130 150 2.338 2.368 2.363 2.367 T131 150 2.337 2.377 2.376 2.375 T132 150 2.313 2.349 2.349 2.348 T133 150 2.365 2.396 2.395 2.395 T134 150 2.342 2.398 2.398 2.397 T135 150 2.355 2.383 2.383 2.382 T248 150 2.107 2.151 2.142 2.140 T249 150 2.322 2.329 2.328 2.328 T250 150 2.303 2.341 2.339 2.339 T251 150 2.329 2.358 2.355 2.355 T252 150 2.314 2.371 2.370 2.369 T253 150 2.274 2.320 2.319 2.318 T254 150 2.330 2.326 2.324 2.323 T255A 150 2.246 2.272 2.270 2.270 T255B 150 2.355 2.379 2.376 2.374 T256 150 2.317 2.348 2.347 2.346 T257 150 2.353 2.351 2.349 2.347 T258 150 2.088 2.137 2.131 2.128 T259 150 2.365 2.368 2.367 2.366 45 TABLE 4.8. (Con’t.) Lab Test Results of Field Cores, Phase II, Group B Sample ID Diameter (mm) CoreReaderTM Gmb Core Dryer Gmb Slow oven Gmb Fast oven Gmb T260 150 2.349 2.373 2.371 2.371 T261 150 2.175 2.218 2.215 2.213 T262 150 2.315 2.361 2.360 2.360 T263 150 2.310 2.358 2.357 2.357 T264 150 2.333 2.376 2.376 2.376 T265 150 2.317 2.354 2.353 2.353 T266 150 2.218 2.280 2.277 2.276 T267 150 2.328 2.372 2.371 2.371 T268 150 2.310 2.365 2.364 2.364 T269 150 2.211 2.231 2.225 2.222 TABLE 4.9. CoreReaderTM Gmb Before and After Sawing of Field Cores, Phase III Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) B32 100 2.243 2.246 A12 100 2.151 2.195 B33 100 2.195 2.204 A13 100 2.217 2.236 B34 100 2.243 2.257 A14 100 2.184 2.183 B35 100 2.255 2.245 A15 100 2.188 2.200 B36 100 2.230 2.235 A16 100 2.189 2.208 B37 100 2.162 2.177 A17 100 2.161 2.209 B38 100 2.275 2.260 A18 100 2.157 2.171 B39 100 2.179 2.202 B23 100 2.199 2.210 B40 100 2.245 2.235 B24 100 2.192 2.218 T136 150 2.154 2.236 B25 100 2.142 2.147 T137 150 2.236 2.312 B26 100 2.168 2.178 T138 150 2.33 2.332 B27 100 2.183 2.186 T139 150 2.364 2.343 B28 100 2.257 2.232 T140 150 2.268 2.267 B29 100 2.245 2.257 T141 150 2.354 2.352 B30 100 2.234 2.244 T142 150 2.511 2.364 B31 100 2.180 2.192 T143 150 2.373 2.352 T128 150 2.220 2.250 46 TABLE 4.9.(Con’t.) CoreReaderTM Gmb Before and After Sawing of Field Cores, Phase III Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) Sample ID Dia. (mm) CRD Gmb (before sawing) CRD Gmb (after sawing) T144 150 2.367 2.313 T129 150 2.148 2.259 T271 150 2.321 2.343 T130 150 2.335 2.338 T272 150 2.185 2.204 T131 150 2.318 2.337 T273 150 2.137 2.160 T132 150 2.298 2.313 T274 150 2.128 2.163 T133 150 2.387 2.365 T275 150 2.318 2.340 T134 150 2.550 2.342 T276 150 2.241 2.261 T135 150 2.396 2.355 T277 150 2.483 2.359 T248 150 2.070 2.107 T278 150 2.300 2.310 T249 150 2.180 2.322 T279 150 2.313 2.348 T250 150 2.303 2.303 T280 150 2.280 2.321 T251 150 2.339 2.329 T281 150 2.146 2.152 T252 150 2.284 2.314 T282 150 2.206 2.254 T253 150 2.258 2.274 T283 150 2.154 2.228 T254 150 2.300 2.330 T284 150 2.376 2.311 T255A 150 2.209 2.246 T285 150 2.254 2.253 T255B 150 2.308 2.355 T286 150 2.265 2.316 T256 150 2.271 2.317 H1 150 2.070 2.181 T257 150 2.338 2.353 H2 150 2.170 2.276 T258 150 2.049 2.088 H3 150 2.259 2.283 T259 150 2.337 2.365 H4 150 2.178 2.339 T260 150 2.315 2.349 H5 150 2.302 2.308 T261 150 2.139 2.175 H6 150 2.234 2.26 T262 150 2.280 2.315 H7 150 2.262 2.354 T263 150 2.491 2.310 H8 150 2.337 2.353 T264 150 2.312 2.333 H9 150 2.318 2.373 T265 150 2.275 2.317 H10 150 2.253 2.244 T266 150 2.194 2.218 H11 150 2.195 2.234 T267 150 2.312 2.328 H12 150 2.282 2.320 T268 150 2.318 2.310 H13 150 2.287 2.311 T269 150 1.558 2.211 47 CHAPTER 5 ANALYSIS OF TEST RESULTS This chapter provides the analysis of the experimental test data. Two different statistical analyses techniques were performed for the evaluation of the CoreDryTM and the CoreReaderTM equipment. The statistical analysis consisted of comparison of means of dry mass and Gmb after each drying process. Statistical approaches of comparing means by Analysis of Variance (ANOVA) for more than two groups of data and ttest for two groups were used throughout the analysis. PHASE I COREDRYTM Dry mass of the sample was used for the evaluation of the CoreDryTM as Gmb is directly related to dry mass and the statistical output is no different than using Gmb. Gmb is the dry mass divided by a constant, equal to ‘SSD massSubmerged mass’, so the distribution of data would be the same. ANOVA with Duncan’s multiple range test, paired ttest and comparisons to the standard precision statements were used as analytical tools for the evaluation of the CoreDryTM apparatus. For analysis purposes, data are grouped into two categories, namely lab compacted samples and field cores. . 48 ANOVA with Duncan’s Test Lab Compacted Samples The lab compacted samples have four sets of Gmb and consequently dry masses which are referred to as methods. The dry masses and their notation are as follows: i) Initial dry mass ( Initial dry) ii) Dry mass after CoreDry (CoreDryTM) iii) Dry mass after slow oven drying ( Slow oven) iv) Dry mass after fast oven drying ( Fast oven) For the evaluation of drying efficiency of CoreDryTM apparatus using lab compacted samples, the dry mass by CoreDryTM is compared with initial dry mass (dry mass after cooling to room temperature), dry mass after slow oven drying and dry mass after fast oven drying. The S3 and S4 mixes consists of samples with two different heights, one 95 mm and 115 mm. The SMA samples were all 115 mm high. For effective comparisons, samples of approximately equal dry mass are necessary. Therefore, ANOVA with Duncan’s multiple range tests are performed for each group for the lab compacted samples, by height. The results of ANOVA with Duncan’s multiple range tests are presented in tables 5.1 and 5.2 for group A samples and in tables 5.3 and 5.4 for group B samples. The ANOVA indicates that there is no statistical difference between initial dry, CoreDryTM, slow oven and fast oven dry mass at a confidence limit of 95% (α = 0.05). The means and results from Duncan’s multiple range tests confirm the results. 49 TABLE 5.1. ANOVA Test Result, Group A, Height=95mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 1 459432.68 459432.68 13635.30 <0.0001 Method 2 45.01 22.51 0.67 0.5250 Mix*Method 2 11.50 5.75 0.17 0.8445 Duncan Grouping* Mean Dry Mass N Method A 3740.4 8 Slow oven A 3737.8 8 Fast oven A 3737.2 8 Initial dry * Means with the same letter are not significantly different. TABLE 5.2. ANOVA Test Result, Group A, Height=115mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 1125034.80 562517.40 9204.86 <0.0001 Method 2 11.49 5.75 0.09 0.9104 Mix*Method 4 8.58 2.15 0.04 0.9976 Duncan Grouping* Mean Dry Mass N Method A 4753.4 22 Slow oven A 4752.7 22 Initial dry A 4752.4 22 Fast oven * Means with the same letter are not significantly different. TABLE 5.3. ANOVA Test Result, Group B, Height=95mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 1 439508.53 439508.53 3762.78 <0.0001 Method 2 3.06 1.53 0.01 0.9870 Mix*Method 2 0.05 0.02 0.00 0.9998 50 Duncan Grouping* Mean Dry Mass N Method A 3736.9 8 CoreDryTM A 3736.2 8 Initial dry A 3736.1 8 Fast oven * Means with the same letter are not significantly different. TABLE 5.4. ANOVA Test Result, Group B, Height=115mm (By Height) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 1106003.14 553001.57 14682.80 <0.0001 Method 2 1.10 0.55 0.01 0.9855 Mix*Method 4 0.72 0.18 0.00 1 Duncan Grouping* Mean Dry Mass N Method A 4756.2 21 CoreDryTM A 4756.0 21 Initial dry A 4755.7 21 Fast oven * Means with the same letter are not significantly different. The following figures, figure 5.1 and 5.2, show the interval plot for the mean dry masses and 95% confidence interval for group A and B lab compacted samples, respectively. 51 Initial dry mass Slow oven Core Dry Fast Oven 4700 4600 4500 4400 4300 Dry mass 4481.93 4483.26 4482.39 4481.8 Interval plot for means 95% CI for the Mean FIGURE 5.1 Interval plot for lab compacted samples (Group A). Initial dry mass Slow oven Core Dry Fast Oven 4700 4600 4500 4400 4300 Dry mass 4474.71 4474.61 4475 4474.44 95% CI for the Mean Interval Plot for means FIGURE 5.2 Interval plots for lab compacted samples (Group B). 52 The Duncan’s multiple range test result presented in tables 5.1 and 5.2 for group A samples, and presented in table 5.3 and 5.4 for group B samples, show that the mean is same for all methods. ANOVA results show that there is no significant interaction of mix type on methods. The mean of initial dry, slow oven, and fast oven dry masses for group A are statistically the same and the mean of initial dry, CoreDryTM, and fast oven dry masses are the same for group B samples. The methods are significantly different by mix which is due to the effect of Gsb on dry mass. The Gsb, and consequently dry mass, can be different for different mixes. The results show that the CoreDryTM method works well for effective drying of lab compacted samples and gives statistically similar results to the oven drying methods of AASHTO T166 and to the initial dry mass. Field Cores Field cut cores have only three dry masses; namely slow oven, CoreDryTM and fast oven which are considered as methods for the statistical analysis. Two different sizes of cores were used in the testing, 100 mm and 150 mm and hence, in the analysis. The ANOVA and Duncan’s tests were performed by group, and the interaction of diameter on methods was checked. The ANOVA and Duncan’s multiple range test results for group A are presented in table 5.5 and the test result for group B are presented in table 5.6. The ANOVA results show the means are same for all methods at a confidence interval of 95 % (α = 0.05). 53 TABLE 5.5. ANOVA Test Result for Field Cores, Group A, (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Diameter 1 52062781.14 52062781.14 101.19 < 0.0001 Method 2 62.28 31.14 0.00 0.9999 Diameter*Method 2 1.95 0.98 0.00 1.0000 Duncan Grouping* Mean Dry Mass N Method A 1879.06 103 Slow oven A 1878.56 103 Core Dry A 1877.77 103 Fast oven * Means with the same letter are not significantly different. TABLE 5.6. ANOVA Test Result for Field Cores, Group B, (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Diameter 1 51440952.65 51440952.65 101.19 < 0.0001 Method 2 105.07 75.62 0.00 0.9999 Diameter*Method 2 0.64 0.32 0.00 1.0000 Duncan Grouping* Mean Dry Mass N Method A 1885.08 116 CoreDryTM A 1883.96 116 Slow oven A 1883.51 116 Fast oven * Means with the same letter are not significantly different. The interval plots for the mean dry mass and 95% confidence interval for group A and B field core samples are presented in figure 5.3 and 5.4, respectively. 54 S low oven Core Dry Fast Oven 2050 2000 1950 1900 1850 1800 1750 1700 Dry mass 1879.06 1878.56 1877.83 Inte rplot for me ans 95% CI for the Mean FIGURE 5.3 Interval plot for field cores (Group A). Slow oven Core Dry Fast Oven 2050 2000 1950 1900 1850 1800 1750 1700 Dry mass 1883.96 1885.08 1883.51 Interval plot for means 95% CI for the Mean FIGURE 5.4 Interval plot for field cores (Group B). 55 The ANOVA and Duncan’s multiple range test results presented in tables 5.5 and 5.6 show that slow oven, CoreDryTM and fast oven dry mass are statistically similar. The ANOVA results also indicate that there is no significant interaction of diameter on methods. The means are statistically different for the two different diameters, which were expected. Based on the ANOVA test results, CoreDryTM produces similar results to the slow and fast oven drying methods for field cores which have greater water absorption than lab compacted samples. Paired tTest Lab Compacted Samples The ANOVA test with Duncan’s multiple range test showed that there was no statistical difference among the methods i.e. initial dry, CoreDryTM, slow oven and fast oven dry mass, and hence the Gmb, for lab compacted samples. When the same set of data was analyzed using a one tail paired ttest for two sample means, a statistical difference at a confidence limit of 95% (α = 0.05) was observed. The onetailed paired ttest was used because the dry mass after a drying method is less than or equal to the dry mass after previous drying. The paired ttest results are presented in table 5.7. 56 TABLE 5.7. Paired ttest Result for Lab Compacted Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Height Initial and Slow 4.39 1.89 1.6E03 Not same. 95 mm, Gr. A Slow and Core 4.33 1.89 1.7E03 Not same. Slow and Fast 4.31 1.89 1.8E03 Not same. Initial and Core 8.71 1.89 2.6E05 Not same. 95 mm, Gr. B Core and Slow 4.53 1.89 1.4E03 Not same. Core and Fast 5.24 1.89 6.0E04 Not same. Initial and Slow 2.84 1.86 1.1E02 Not same. 115 mm, Gr. A Slow and Core 2.24 1.86 2.8E02 Not same. Slow and Fast 2.28 1.86 2.6E02 Not same. Initial and Core 3.21 1.86 6.2E03 Not same. 115 mm, Gr. B Core and Slow 2.58 1.86 1.6E02 Not same. Core and Fast 2.82 1.86 1.1E02 Not same. Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass According to the paired ttest results presented in table 5.7, all methods are statistically different. Hence, the CoreDryTM apparatus does not produce similar dry mass as obtain from slow oven or fast oven drying methods for laboratory compacted samples. Table 5.7 also indicates that slow oven dry mass is statistically different than rest of the methods. The statistical difference between the methods in paired ttest is due to the power of the paired ttest compared to the ANOVA (ftest). Field Cores The ANOVA test with Duncan’s multiple range tests showed no statistical difference among all of the methods i.e. CoreDryTM, slow oven and fast oven dry mass for field core samples. When the same set of data was analyzed using a one tail paired ttest for two sample means, a statistically significant difference at a confidence limit of 95% (α = 0.05), was found . The paired ttest results are presented in table 5.8. 57 TABLE 5.8. Paired ttest Result for Field Core Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Group Gr. A Slow and Core 4.36 1.66 1.5E05 Not same. Slow and Fast 7.31 1.66 3.1E11 Not same. Gr. B Core and Slow 9.88 1.66 2.4E17 Not same. Core and Fast 10.68 1.66 3.3E19 Not same. Note: Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass The statistical difference between the methods was found when compared by paired ttest for field cores. All of the methods are statistically different. Hence, the CoreDryTM apparatus does not produce similar dry mass as obtain from slow oven or fast oven drying methods for field cut core samples. Practical Significance Lab Compacted Samples Sometimes, statistically similar results may have a practical difference and statistically different results may not have any practical difference. To evaluate the practical differences among methods, the difference in means between consecutive methods were calculated and compared with the AASHTO T166 requirement for dry state of mass, which is mass loss less than 0.05 % of total mass. The results are presented in table 5.9 for lab compacted samples. The results show that the difference is less than 0.05 percent. Therefore, no practical difference was found for lab compacted samples. The dry mass obtained from CoreDryTM apparatus can be used for laboratory analysis of HMA samples. 58 TABLE 5.9. Practical Significance of the Test Result for Lab Compacted Samples Sample Type Gr. Method Mean dry mass Comparison between Mean % difference Remarks Initial 4472.6 Initial Vs Slow 0.031 No difference Slow 4474.0 Slow Vs Core 0.020 No difference Core 4473.1 Slow Vs Fast 0.034 No difference A Fast 4472.5 Initial 4464.3 Initial Vs Core 0.007 No difference Core 4464.6 Core Vs Slow 0.009 No difference Slow 4464.2 Core Vs Fast 0.006 No difference Lab Compacted B Fast 4464.0 Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass Field Cores To evaluate the practical differences among methods for field cores, the same procedure used for lab samples was followed. The mean difference between consecutive methods were calculated and compared with the AASHTO T166 requirements for dry state of mass, which is mass loss less than 0.05 % of total mass, as in case of lab compacted samples. The results are presented in table 5.10. 59 TABLE 5.10. Practical Significance of the Test Result for Field Cores Sample Type Gr. Method Mean dry mass Comparison between Mean % differenc e Remarks Slow 1813.3 Slow Vs Fast 0.050 No difference Core 1813.1 Core Vs Fast 0.039 No difference Fast 1812.4 Slow Vs Core 0.011 No difference A Core 1758.6 Core Vs Fast 0.045 No difference Slow 1757.9 Slow Vs Fast 0.006 No difference Field Cores B Fast 1757.8 Core Vs Slow 0.040 No difference Note: Initial: Initial dry mass; Core: CoreDryTM mass; Slow: slow oven dry mass; Fast: fast oven dry mass The difference between the methods was equal to or less than 0.05 %. Therefore; there is no practical difference between the slow and fast method and between CoreDryTM and fast method. The CoreDryTM can be used to determine the dry mass for Gmb determination. PHASE II COREREADERTM This phase of the analysis is the evaluation of CoreReaderTM apparatus. The analysis in this phase includes comparison of the Gmb obtained from CoreReaderTM to Gmb obtained by conventional water displacement methods of AASHTO T166. This was accomplished by the statistical comparison of Gmb obtained from CoreReaderTM to the Gmb obtained by conventional AASHTO T166 methods and the Gmb obtained from the CoreDryTM dry mass. To analyze the comparisons between the methods, ANOVA with Duncan’s multiple range tests and paired ttests were used throughout the analysis. In addition, if the CoreReaderTM Gmb was found different than the Gmb obtained from 60 water displacement method, an attempt will be made to develop a correlation. For the effective analysis and correlation development, lab compacted and field cores are treated separately, similar to phase I analysis. ANOVA with Duncan’s Test Lab Compacted Samples For the lab compacted samples, the dry mass used in phase I were used to calculate the Gmb in AASHTO T166 methods. The lab compacted samples have five sets of Gmb. The five categories and their notations for analysis are as follow: i) AASHTO T166 Gmb( T166) ii) CoreDryTM Gmb (CoreDryTM) iii) Slow oven Gmb ( Slow oven) iv) Fast oven Gmb ( Fast oven) v) CoreReaderTM Gmb (CoreReaderTM) In above categories, T166 Gmb is the conventional bulk specific gravity of lab compacted samples calculated using the volume obtained by water displacement method and initial dry mass of sample before submerging in water in accordance to AASHTO T166. Similarly, CoreDryTM, Slow oven and Fast oven Gmb are obtained by using the volume by water displacement and dry mass after each respective method. An ANOVA with Duncan’s multiple range test were performed for the whole set of data for each group (Group A and Group B) of lab compacted samples. The results of ANOVA with Duncan’s multiple range tests were performed at a confidence limit of 95% (α = 0.05). The results for lab compacted samples for group A and group B are 61 presented in tables 5.11 and 5.12, respectively. The results show that CoreReaderTM Gmb is statistically different from the other test methods. ANOVA results show there is no interaction of type of mix on methods. The data in this phase need not to be analyzed by height as analysis is performed for Gmb, which normalizes the dry mass data. TABLE 5.11. ANOVA Test Result for Lab Compacted Samples, Group A (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 0.31931 0.15966 97.41 < 0.0001 Method 3 0.02497 0.00832 5.08 0.0025 Mix*Method 6 0.00132 0.00022 0.13 0.9916 Duncan Grouping* Mean Gmb N Method A 2.356 30 Slow oven A 2.355 30 Fast oven A 2.355 30 T166 B 2.320 30 CoreReaderTM * Means with the same letter are not significantly different. TABLE 5.12. ANOVA Test Result for Lab Compacted Samples, Group B (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Mix 2 0.27770 0.13885 77.32 < 0.0001 Method 3 0.02012 0.00671 3.74 0.0135 Mix*Method 6 0.00027 0.00005 0.03 0.9999 Duncan Grouping* Mean Gmb N Method A 2.367 29 CoreDryTM A 2.366 29 T166 A 2.366 29 Fast oven B 2.336 29 CoreReaderTM * Means with the same letter are not significantly different. 62 The ANOVA test results and the Duncan’s multiple range tests presented in tables 5.11 and 5.12 show that Gmb obtained by CoreReaderTM is statistically different than Gmb obtained by water displacement methods. The Gmbs are different for mix type but there is no significant interaction on methods, therefore, it was not necessary to perform the ANOVA by mix type. Field Cores Field cores consist of four types of Gmb namely, CoreReaderTM Gmb, slow oven Gmb, CoreDryTM, and fast oven Gmb. To compare the Gmb by CoreReaderTM, ANOVA with Duncan’s multiple range test was used and the four Gmbs mentioned above were compared. In this case, there is no need to analyze the data by diameter as calculation of Gmb normalizes the data. Therefore, oneway ANOVA with Duncan’s multiple range tests at a confidence limit of 95% (α = 0.05) was performed for group A and group B samples. The test results are presented in tables 5.13 and 5.14 for group A and B field cores, respectively. TABLE 5.13. ANOVA Test Result for Field Cores, Group A (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Method 2 0.13106 0.06553 3.13 0.0451 Duncan Grouping* Mean Gmb N Method A 2.292 103 Slow oven A 2.269 103 Fast oven B 2.242 103 CoreReaderTM * Means with the same letter are not significantly different. 63 TABLE 5.14 ANOVA Test Result for Field Cores, Group B (By Group) Source Degrees of Freedom Sum of Squares Mean Square F Ratio Prob.>F Method 2 0.14853 0.07427 19.48 <0.001 Duncan Grouping* Mean Gmb N Method A 2.301 116 CoreDryTM A 2.301 116 Fast oven B 2.257 116 CoreReaderTM * Means with the same letter are not significantly different. The ANOVA test with Duncan’s multiple range test results showed CoreReaderTM Gmb is statistically different than other methods for both groups of field core samples. The Gmb obtained from slow oven, CoreDryTM and fast oven drying were found statistically same, which indicates no difference in these methods, as found in the phase I analysis. Paired tTest Lab Compacted Samples The paired ttest for two sample means between CoreReaderTM Gmb and either AASHTO T166 Gmb or fast oven Gmb, in case of lab compacted samples, showed CoreReaderTM Gmb is statistically different. The one tail paired ttest at a confidence limit of 95% (α = 0.05) for lab compacted samples is presented in table 5.15. 64 TABLE 5.15. Paired ttest Result for Lab Compacted Samples Group Comparison between tstatistic tcritical P value Comments on means By Group Gr. A CR and T166 12.40 1.70 4.1E13 Not same. CR and Fast 12.28 1.70 2.6E13 Not same. Gr. B CR and T166 10.68 1.70 1.1E11 Not same. CR and Fast 10.66 1.70 1.1E11 Not same. By Height 115 mm, Gr. A CR and T166 6.32 1.86 1.1E04 Not same. CR and Fast 6.23 1.86 1.2E04 Not same. 115 mm, Gr. B CR and T166 4.53 1.86 9.6E04 Not same. CR and Fast 4.54 1.86 9.6E04 Not same. 95 mm, Gr. A CR and T166 12.97 1.89 1.9E06 Not same. CR and Fast 13.55 1.89 1.4E06 Not same. 95 mm, Gr. B CR and T166 8.1721 1.89 4.0E05 Not same. CR and Fast 8.2001 1.89 3.9E05 Not same. Note: CR: CoreReaderTM Gmb; Fast: Fast oven Gmb; T166: AASHTO T166 Gmb. Field Cores The same approach for comparison of CoreReaderTM Gmb and fast oven Gmb was applied to the field cores. The one tail paired ttest results for field cores at a confidence limit of 95% (α = 0.05) are presented in table 5.16. The paired ttest results show that there is a statistical difference between Gmb obtained from CoreReaderTM and AASHTO T166. 65 TABLE 5.16. Paired ttest Result for Field Core Samples Group Comparison between tstatistic tcritical Pvalue Comments on means By Group Gr. A CR and Fast 1.2765 1.6599 0.1023417 Are same Gr. B CR and Fast 9.3211 1.6582 4.953E16 Not same. CR and F By ast 19.859 1.666 1.873E31 Not same. Diameter 150 mm, Gr. A CR and Fast 7.6961 1.6628 1.084E11 Not same. 150 mm, Gr. B CR and Fast 12.481 1.7011 2.933E13 Not same. 100 mm, Gr. A CR and Fast 7.1918 1.7011 3.963E08 Not same. 100 mm, Gr. B Note: CR: CoreReaderTM Gmb; Fast: Fast oven Gmb; The paired ttest for lab compacted samples showed a statistical difference between CoreReaderTM Gmb and the rest of the methods. For field cores, the CoreReaderTM Gmb and fast oven Gmb are statistically similar for Group A cores when both 100 and 150 mm diameter samples are analyzed together. When the field cores were tested for paired ttest by breaking into two groups by diameter, CoreReaderTM Gmb was found to be different than fast oven Gmb. Practical Significance Lab Compacted Samples Practical significance is as important as statistically similar results. Test results can have no practical difference and show statistical difference. To evaluate the practical differences between AASHTO T166 Gmb and CoreReaderTM Gmb, the AASHTO precision guideline was used. According to AASHTO T166 (3), the difference between 66 Gmb by two consecutive tests should not be greater than 0.02, the acceptable limit for laboratory Gmb determination. In this case, only AASHTO T166 Gmb is used to compare with CoreReaderTM, as previous section has already shown that AASHTO T166, slow oven, CoreDryTM, and fast oven Gmb are similar. Practical significance check is presented in table 5.17 for lab compacted samples. Results show that the difference in Gmb exceeds the acceptable limit for test results and, therefore, the methods produce different results. TABLE 5.17. Practical Significance of the Test Result for Lab Compacted Samples Sample Type Gr. Method Mean Gmb Comparison between Mean differenc e Remarks AASHTO T166 2.355 A CoreReaderTM 2.320 AASHTO T166 and CoreReaderTM 0.035 Are different. Lab Samples AASHTO T166 2.367 B CoreReaderTM 2.336 AASHTO T166 and CoreReaderTM 0.031 Are different. Field Cores The same approach of evaluating the practical significance of lab compacted samples was applied to the field cores. The mean difference between the CoreReaderTM and fast oven Gmb were calculated and compared with the AASHTO T166 precision requirement of a difference of less than 0.02. The results are presented in table 5.18. 67 TABLE 5.18. Practical Significance of the Test Result for Field Core Samples Sample Type Gr. Method Mean Gmb Comparison between Mean difference Remarks CoreReaderTM A 2.241 Fast oven 2.269 CoreReaderTM and Fast oven 0.028 Are different. Field cores CoreReaderTM 2.257 B Fast oven 2.305 CoreReaderTM and Fast oven 0.048 Are different. For field cores, the CoreReaderTM Gmb produces different results than AASHTO T166 fast oven Gmb. The ANOVA with Duncan’s multiple range tests and paired ttest showed CoreReaderTM Gmb is different than Gmb obtained from AASHTO T166 methods and CoreDryTM apparatus for both lab compacted and field core samples. The CoreReaderTM Gmb is outside the acceptable range of two results listed in AASHTO T166. Thus, the above tests indicate that the CoreReaderTM apparatus does not produce the same results as AASHTO T166. PHASE III Effect of Parallel Faces on CoreReaderTM Gmb The test procedure for the CoreReaderTM says sample ends need to be parallel with smooth edges. To evaluate the effect of parallel faces on CoreReaderTM Gmb, field cores with one end uneven or irregular were first tested in CoreReaderTM and again with both faces parallel by sawing one side. A less powerful ttest assuming equal variance, which is the same as ftest for two methods, and the more powerful paired t test for two sample means, were used to evaluate the difference. Table 5.19 shows the comparison using ttest and paired ttest at a confidence limit of 95 % (α = 0.05). 68 TABLE 5.19. ttest Results for Effect of Parallel Faces on CoreReaderTM Gmb Type of test tstatistic tcritical Pvalue Comments on means ttest, assuming equal variances 1.608 1.661 0.0548 Means are same Paired ttest, two sample for means 2.583 1.653 0.0057 Means are not same. The ttest showed there is no statistical difference between Gmb before and after sawing the cores. The paired ttest, which is a more powerful test than the ttest, showed that there is a significant difference between the two Gmbs. The mean and standard deviation of the CoreReaderTM Gmb for cores with one face not smooth (i.e. having higher heights) is 2.249 and 0.1169 whereas for both faces smooth (i.e. having smaller heights) are 2.279 and 0.067. The difference in means value is 0.030, which is greater than the acceptable range of two results of 0.02, as listed in AASHTO T166. In this case the samples with both faces parallel also had a lower standard deviation, 0.067 compared to 0.1169. It appears that the parallel face requirement for CoreReaderTM testing is justified. Figure 5.5 indicates that most of the data are above the line of equality, indicating that having both faces parallel results in slightly higher Gmb values. 69 CRD Gmb before vs CRD Gmb after sawing 2.05 2.1 2.15 2.2 2.25 2.3 2.35 2.4 2.05 2.15 2.25 2.35 CRD Gmb, before sawing CRD Gmb, after sawing .. After sawing Linear (Line of equality) FIGURE 5.5 Before vs. after sawing plot for CoreReaderTM Gmb. CORRELATION BETWEEN COREREADERTM AND AASHTO T166 Gmb Lab Compacted Samples The previous statistical analysis showed that CoreReaderTM Gmb is statistically different than AASHTO T166 Gmb. However, this does not mean that the CoreReaderTM cannot be successfully used to determine the Gmb of HMA samples. Many state DOTs allow the use of nuclear and/or non nuclear density meters to determine the inplace density of HMA pavements if a correlation is established between Gmb from cores of the pavement and gauge results. To develop the correlations between CoreReaderTM Gmb and AASHTO T166, Gmb the field cores and lab samples were used. The lab compacted 70 S3 and S4 mixes were compacted to two VTM contents only, and cannot be used to establish a correlation. The lab compacted SMA samples contained a wide variation in Gmb, and a meaningful correlation could be developed. The relationship is shown in figure 5.6. The relation has a goodness of fit (R2) of 0.94 indicating that a good approximation of T166 Gmb can be made. AASHTO T166 Gmb can be approximated using the CoreReaderTM Gmb, using the following relationship. T166= 0.7469 * CR + 0.6244 Where, T166= AASHTO T166 Gmb CR= CoreReaderTM Gmb Lab Mix (SMA) y = 0.7469x + 0.6244 R2 = 0.9359 2.220 2.240 2.260 2.280 2.300 2.320 2.340 2.360 2.380 2.400 2.420 2.220 2.270 2.320 2.370 2.420 CoreReader TM Gmb T166 Gmb . T 166 gmb Line of equality FIGURE 5.6 Correlation of T166 Gmb and CoreReaderTM Gmb for SMA. 71 Field Cores For field cores, the CoreReaderTM Gmb was found to be statistically different from AASHTO T166 Gmb by both the ftest and ttest. A regression plot of CoreReaderTM and AASHTO T166 Gmb (fast oven Gmb) for 100 mm and 150 mm samples together, is presented in figure 5.7. Field cores y = 0.8753x + 0.3266 R2 = 0.8601 2.000 2.050 2.100 2.150 2.200 2.250 2.300 2.350 2.400 2.450 2.000 2.100 2.200 2.300 2.400 CoreReader TM Gmb Fast oven Gmb . Fast oven Gmb Line of equality FIGURE 5.7 Correlation of T166 fast oven Gmb and CoreReaderTM Gmb for 100 mm and 150 mm field cores. The value of T166 Gmb (fast oven Gmb) using CoreReaderTM Gmb for field cores can be approximated, using the following relationship, T166 fast oven Gmb = 0.8753 * CR + 0.3226 Where, CR= CoreReaderTM Gmb. The relationship has a goodness of fit (R2) of 0.86. 7 2 CHAPTER 6 CONCLUSIONS AND RECOMMEDDATIONS CONCLUSION Based on the test results obtained and analysis of the test data, the following conclusions were made for phase I, phase II and phase III evaluations. Phase I CoreDryTM 1. The ANOVA test, which is considered a less powerful test than paired ttest, showed that initial dry mass, slow oven dry mass, dry mass after CoreDryTM and fast oven dry mass are statistically similar. ANOVA results also indicated that there is no significant interaction between type of mix and sample diameter on drying methods. This was true for both laboratory compacted and field core samples. 2. Paired ttest analysis showed that the CoreDryTM, slow oven and fast oven dry masses are not statistically similar. 3. Besides the statistical analysis, practical significance of the difference in dry masses was checked according to the AASHTO T166 requirement of a mass loss of less than 0.05 % between the two consecutive drying operations. There was no practical difference found between the slow and fast methods and between the CoreDryTM and fast method for both lab compacted and field core samples. 7 3 4. Based on the statistical and practical analysis of the test data, the CoreDryTM can be considered as equivalent to the AASHTO T166 method A and method C, which are slow oven drying method and fast oven drying method, respectively. Phase II CoreReaderTM 1. The ANOVA ftest and paired ttest analysis showed that the Gmb obtained by CoreReaderTM apparatus is statistically different than Gmb obtained by AASHTO T166 methods at a significance level of 95%. 2. The CoreReaderTM Gmb was also statistically different than the Gmb obtained by using the dry mass obtained from the CoreDryTM. 3. A practical difference in Gmb greater than 0.020, was also found between the CoreReaderTM Gmb and Gmb obtained from AASHTO T166 methods. 4. Based on the statistical and practical analysis, the CoreReaderTM apparatus cannot be considered as a direct substitute for the AASHTO T166 methods of Gmb determination. Detail study is required before considering it as an alternative method of Gmb determination. 5. A correlation similar to what is used for field nuclear density devices can be used to calculate AASHTO T166 Gmb using CoreReaderTM Gmb for lab compacted and field core samples. Phase III Effect of Parallel Faces on CoreReaderTM Gmb To check the effect of irregular and uneven faces on CoreReaderTM Gmb, paired ttest, and ttest assuming equal variances were used. Paired ttest showed that there is a significant difference between the two Gmbs whereas ttest showed that there is not an effect of unparallel faces on CoreReaderTM Gmb. The difference in mean value was out 7 4 of acceptable limit of 0.020, as listed in ASHTO T166. Hence, there is significant effect of uneven and unparallel faces on CoreReaderTM Gmb and the requirement for smooth parallel faces should be followed. RECOMMENDATIONS 1. The CoreDryTM apparatus can be used for the drying of lab compacted as well as field core samples for the Gmb determination. 2. CoreReaderTM apparatus did not produce similar results to AASHTO T166. If desire to use, correlations should be developed similar to those used when using the filed nuclear density devices. 3. It is necessary to saw the field core samples to make its faces smooth and parallel for the Gmb determination by CoreReaderTM apparatus. 7 5 REFERENCES 1. Application Brief Troxler Model 3660, CoreReaderTM. Laboratory Nuclear Density Device, Troxler, http://www.troxlerlabs.com/pdf%20files/3660appbrief.pdf. Accessed July 16 2007. 2. User Guide, InstroTek® CoreDryTM Apparatus, http://www.instrotek.com/coredry.htm. Accessed July 15 2007. 3. “Bulk Specific Gravity of Compacted HotMix Asphalt Using Saturated Surface Dry Specimens, AASHTO Designation: T166.”Standard Specifications for Transportation Materials and Methods of Sampling and Testing, Twentyfifth Edition, Part 2A, Tests, American Association of State Highway and Transportation officials, Washington, D.C., 2005. 4. “Standard Test Method for Bulk Specific Gravity and Density of NonAbsorptive Compacted Bituminous Mixtures”, ASTM Designation: D2726. Annual Book of ASTM Standards, Section four, Volume 05.03., American Society for Testing and Materials, West Conshohocken, PA., 2005. 5. Hall, Kevin D., Kevin, “Evaluation of Drying Efficiency for HotMix Cores Using Vacuum Drying Method.” Compendium of Papers, 86th Annual Meeting of the Transportation Research Board. CDROM. Transportation Research Board, National Research Council, Washington, D.C., January 2007. 6. Troxler CoreReaderTM Model 3660. www.troxlerlabs.com. Accessed July 16 2007. 7. Retzer, N., “Review and Research of Instrotek’s CoreDry® Report”, Materials and Geotechnical Branch, Colorado Department of Transportation, Denver, Colorado, 2006. 8. Williams, Stacy G., “Bulk Specific Gravity Measurements of 25.0 mm and 37.5 mm CoarseGraded Superpave Mixes.” Compendium of Papers, 86th Annual Meeting of the Transportation Research Board. CDROM. Transportation Research Board, National Research Council, Washington, D.C., January 2007. 9. Malpass and Khosla, “Evaluation of Gamma Ray Technology for the Measurement of Bulk Specific Gravity of Compacted Asphalt Concrete Specimens.” Journal, Association of Asphalt paving Technologists, Association of Asphalt Paving Technologists. Vol. 70, p352, 2001 VITA Gyanendra Pokhrel Candidate for the Degree of Master of Science Thesis: VALIDATION OF COREDRYTM AND COREREADERTM APPRATUS Major Field: Civil Engineering Biographical: Personal Data: Born on December 28th, 1980 in Nepal. Education: Completed the requirements for the Master of Science in Civil Engineering at Oklahoma State University, Stillwater, Oklahoma in December, 2007. Experience: Research Assistant, Department of Civil Engineering, Oklahoma State University, Stillwater, February 2006December 2007 Professional Memberships: Member of Honor society, Phi Kappa Phi, Oklahoma State University. Member of American Society of Civil Engineers, Student Chapter at Oklahoma State University. Member of Nepal Engineering Council, Nepal. ADVISER’S APPROVAL: Dr. Stephen A. Cross Name: Gyanendra Pokhrel Date of Degree: December, 2007 Institution: Oklahoma State University Location: Stillwater, Oklahoma Title of Study: VALIDATION OF COREDRYTM AND COREREADERTM APPARATUS Pages in Study: 75 Candidate for the Degree of Master of Science Major Field: Civil Engineering Scope and Method of Study: The evaluation of CoreDryTM, and CoreReaderTM apparatus was completed based on the test results of laboratory prepared ODOT S3, S4 and SMA mixes and field cores of 100 mm and 150 mm. The CoreDryTM apparatus was evaluated by comparing the dry mass obtained using the CoreDryTM apparatus with dry mass obtained by AASHTO T166 drying methods. The evaluation of CoreReaderTM was completed by comparing the Gmb obtained using CoreReaderTM apparatus and Gmb obtained by AASHTO T166 procedures. The comparison of means of dry masses and Gmbs was performed by statistical tests such as ANOVA, paired ttest, and ttest. Findings and Conclusions: The CoreDryTM apparatus can be used for the drying of lab compacted as well as field core samples for the Gmb determination. CoreReaderTM apparatus did not produce similar results to AASHTO T166. If desire to use, correlations should be developed similar to those used when using the filed nuclear density devices. It is necessary to saw the field core samples to make its faces smooth and parallel for the Gmb determination by CoreReaderTM apparatus. 



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