Dynamic Mechanical Analysis of Asphalt Pavement Based on Cross-isotropic Properties

Considering the effect of anisotropic properties of asphalt mixture,aggregate base and soil subgrade on the asphalt pavement and based on comprehensive studies at home and abroad,the finite element numerical analysis and cross-isotropic coefficient under the assumption of linear elastic layer were introduced to establish a 3D pavement structure model.By using the finite element software ABAQUS,subroutine DLOAD was further developed to simulate a vertical moving load with non-uniform distribution.The moving load action,boundary condition and material parameters were given.And the comparative analysis of the differences of vertical,longitudinal and transverse strains of the moving load under isotropic and cross-isotropic conditions was carried out.The results show that when considering the cross-isotropic behavior of asphalt pavement,the currently-adopted design standard is comparably insecure and the pavement design based on isotropic elasticity underestimates the strains related to permanent deformation and fatigue cracking failure.