Transversely Isotropic Asphalt Pavement Structural Dynamic Response Analysis

The mechanical behaviors of pavement structure layers under the load are different, there are great sensitivity and strong direction dependence for aggregate bases and subbases on the role of force. Using transversely isotropic elastic model to predict aggregate bases and subbases, and vehicles dynamic load to instead of the traditional static load, can better predict the pavement performance, which is a very important significance to long-life pavement structure design.This text established the three-dimensional finite element model of transversely isotropic subgrade under FWD pulse load. Based on the basic principles of finite element dynamic loads, the deflection of the subgrad surface of each sensor at different distances from the center point, the load center stress at different depths, and the effects of the subgrade material anisotropy to them were analyzed and assessed under FWD load. Moving load is more realistic than static load, and predicted results are closer to the actual response of subgrade condition, which provides some basis to the pavement engineering structures construction and the further study.Next, considering the anisotropy of aggregate base, the isotropic elastic of other layers, establishing 3D finite element model of three-layer elastic system of asphalt pavements based on transversely isotropic gravel under moving load to study the dynamic response of asphalt pavement structure layers.Finally, considering the anisotropy of subbases and the isotropic elastic of other layers, the effects of transversely isotropic, different types and sizes to surface deflection, tensile stress at the bottom of graded aggregate base and compressive stress at the top of the subbases on the load center were discussed when the dynamic load run to the central road, which is a good guide for overload control and service life extension.