沥青混合料三轴动态模量的预测方法研究

对SMA-13,Sup-20和Sup-253种沥青混合料进行了不同温度、围压和加载频率下的动态模量试验,并对利用点–斜率法和斜率–比例法(由中间点和由边缘点)预测三轴动态模量的效果进行了研究.结果表明,同一频率时,不同温度下的三轴动态模量与相应的体积应力之间呈线性关系,而且不同围压下的直线斜率几乎相同.利用点–斜率法和斜率–比例法预测三轴动态模量精度均很高,能满足工程应用的需要.利用点-斜率法仅需进行一个中间参考温度下的有围压试验,需要进行的试验量小,容易实现.该研究为更好地利用沥青混合料的三轴动态模量提供了基础.

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.