Study on methods for predicting triaxial dynamic modulus of asphalt concretes

In this study,dynamic modulus tests were performed on three asphalt mixtures,SMA13,Superpave20 and Superpave25,at various confining pressures,temperatures,and loading frequencies.And the accuracy of using point-slope method and slope-proportion method to predict triaxial dynamic modulus was evaluated.The results show that triaxial dynamic modulus correlates linearly with bulk stress,and the slopes at various confining pressures are parallel.The point-slope method and slope-proportion method can accurately predict the triaxial dynamic modulus,and can be used for engineering purposes.The point-slope method requires triaxial testing at only one temperature,and thus reduces the test matrix.This study provides useful tools for better utilizing triaxial dynamic modulus.