Master of Science in Civil Engineering (MSCE)
Civil and Environmental Engineering
The objective of this study was to develop a framework for performance-based specifications (PBS) which rely on the fundamental mechanistic asphalt mixture properties as performance predictors, verified to actual field performance, to compliment current QC/QA specifications for Louisiana. Nine asphalt paving projects were selected across the state with a total of 14 pavement sections that included 21 asphalt mixtures. A suite of laboratory tests using the Hamburg loaded-wheel tracking (LWT) test and the Semi-Circular Bending (SCB) were performed to evaluate the rutting and cracking resistance, respectively. In addition, the Indirect tensile dynamic modulus test (IDT E*) was conducted to evaluate the visco-elastic properties of the asphalt mixtures which were used as material input in the Mechanistic-Empirical Pavement Design Guide (MEPDG) software to predict the 20-year projected distresses. The field distress data were obtained from Louisiana Pavement Management System (LA-PMS) for the selected projects to conduct a comparative analysis with the laboratory measured performance properties. It was observed that most of the mixtures evaluated for LWT and SCB test methods performed well; low rut depths indicated better rut resistance and higher critical strain energies (Jc) values indicated better fracture resistance. The rut depths obtained from LWT test and MEPDG 20-year projection were observed to be in good accordance. SCB Jc was compared to PMS measured combined cracking, alligator cracking index, and random cracking index. Decent correlations were observed between these comparisons with R2 values of 0.55, 0.56, and 0.83. Additional statistical analyses, performed to identify the relationship between the laboratory and field performance parameters, consistently revealed the LWT rut depth and SCB Jc as one of the significant independent variables that affect the field rutting and cracking performance. According to a comparison analysis between the standard and pseudo PBS for three new projects, the rutting performance predictions by the two approaches agreed well. According to findings of this research, it can be concluded that a simplified performance based specification (i.e., Pseudo PBS) procedure, which include LWT and SCB tests, can be added to the current QC/QA specification to better guarantee the long term performance of Louisiana asphalt pavements.
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Release the entire work immediately for access worldwide.
Challa, Harshavardhan, "Framework Development For A Performance-Based Specifications For Asphaltic Concrete Pavements" (2014). LSU Master's Theses. 562.