基于无约束共振法沥青混合料动态模量试验研究

动态模量是沥青路面设计的重要参数，但传统的沥青混合料动态模量试验过程复杂、耗时，而且实际路面钻取的芯样尺寸往往无法满足其试验要求。为解决上述问题，基于沥青混合料圆柱体试件(L/D＜0.5)的无约束自由振动，提出一种快速、无损的沥青混合料动态模量试验方法，分析无约束共振法的试验原理，研究传感器布置点位以及试件尺寸对试验结果的影响，通过重复加载法试验验证无约束共振法与传统试验方法的相关性。结果表明，传感器布置点以及试件尺寸均不会对试验结果造成显著影响，同时无约束共振法与重复加载法具有很好的相关性。

Experimental study on dynamic modulus of asphalt mixture based on free-free resonant test

The dynamic modulus is one of the most important parameters in asphalt pavement design, but the traditional dynamic modulus test of asphalt mixture is complex and time-consuming, and moreover, the drilling core sample size in practical pavement usually cannot meet the requirements of the test in most cases. In order to solve the problem above, based on the free-free resonant test of cylindrical asphalt mixture samples (L/D<0.5), a rapid and nondestructive testing method was presented to measure the dynamic modulus of asphalt mixture. In this work, the principle of free-free resonant testing method was analyzed, and the effects of accelerometer placement and specimen size on the testing results of dynamic modulus were studied. Furthermore, the correlation between the free-free resonant testing method and the conventional testing method was validated based on the repeated loading testing. Research results show that both accelerometer placement and specimen size shall not remarkably affect the free-free resonant testing results, and the free-free resonant testing method has a good correlation with the repeated loading testing method.