硬质沥青混合料动态间接拉伸试验研究

基于动态测定方法确定的沥青混合料的参数能真实反映沥青混合料对运动车辆荷载的响应，并能正确表现沥青混合料本身的粘弹性性质等优点，利用英国Cooper NU-14多功能沥青材料试验机测定了30^#硬质沥青混合料的动态间接拉伸劲度模量，对试验结果进行了二元方差分析及非线性拟合，分析了级配、油石比、结合料类型和试验温度对动态间接拉伸试验的影响。结果表明：30^#硬质沥青混合料具有很高的动态间接拉伸劲度模量，用于沥青路面的下面层可减小其底面的拉应变；级配、油石比、试验温度和沥青针入度均对沥青混合料的动态间接拉伸劲度模量有显著的影响。

Study on Dynamic Indirect Tensile Test of Hard Asphalt Mixture

The index of asphalt mixture verified by the dynamic measurement can really reflect the response of asphalt mixture to the vehicle loading,and have the advantage to correctly show the visco-elastic nature of asphalt mixture.Employing multi-functional asphalt materials test machine imported from England,the dynamic indirect tensile stiffness modulus of No.30 hard asphalt mixture was measured,the test data were studied by two variance analysis and nonlinear regression,and the influence of gradation,asphalt aggregate ratio,asphalt type and test temperature on the dynamic indirect tensile test were analyzed.The results show that(1) No.30 hard asphalt mixture has very high dynamic indirect tensile stiffness modulus,using it in the lower layer of asphalt pavement can reduce the tensile strain;(2) gradation,asphalt aggregate ratio,temperature and penetration of asphalt all has notable influence on the dynamic indirect tensile stiffness modulus of asphalt mixture.