Statistical Evaluation of the Effects of Mix Design Properties on Performance Indices of Asphalt Mixtures

A variety of testing and performance index parameters are available to assess the asphalt mixture performance with respect to different structural distresses. However, because of continuous improvements in asphalt material production and construction techniques, it is necessary to regularly evaluate the correlation of the performance index parameters with mixture design properties. It is also important to determine the correlation between index parameters from different tests to help save time and financial resources by making engineering-based adjustments to the mixture design before conducting multiple tests. This study explores the statistical correlation between mixture design properties and performance index parameters as well as the correlations among the performance index parameters from different tests. A total of 14 commonly used asphalt mixtures in New Hampshire were evaluated using the complex modulus (E*), resilient modulus (M-r), direct tension cyclic fatigue (S-VECD), Semicircular bend Illinois flexibility index (SCB-IFIT), and disk-shaped compact tension (DCT) tests to assess the correlations between various performance indices and mix design properties. The results indicate that the aggregate fractions that pass 4.75 mmand 75 mu m sieve sizes, the binder's useful temperature interval, and recycled asphalt content significantly affect most of the index parameters. Medium-to-high correlations were observed between S-VECD, DCT, and SCB-IFIT with respect to different index parameters.