Abstract:In order to study the dynamic deformation characteristics of subgrade filler of coarse grained soils for high speed railway, the consolidated undrained triaxial tests were carried out by large-scale triaxial test system. Firstly, based on Hardin-Drnevich skeleton curve, the dynamic shear stress-strain curves for loading and unloading were constituted by Masing rules, and the equations of incremental tangent shear modulus of the skeleton curve and hysteresis curves were derived. Using the secondary development platform of ABAQUS, the nonlinear dynamic model subprogram based on Hardin-Drnevich skeleton curve and Masing rules of coarse grained soil was compiled. Study results show the nonlinear dynamic model fit triaxial test results well as the program code was applied to dynamic response analysis of high speed railway. Compared to Mohr-Coulumb constitutive model, the nonlinear dynamic constitutive model can reflect dynamic response characteristics of railway subgrades better.