DYNAMIC FINITE ELEMENT ANALYSIS OF REINFORCED AND UNREINFORCED PAVEMENTS OVER SOFT CLAY

摘要

In order to study the dynamic response of reinforced and unreinforced pavements on soft clay under traffic loading, cyclic triaxial tests were first conducted to investigate the effects of initial deviator stress, loading frequency, overconsolidation ratio, and cyclic stress ratio on softening behavior of clay. The empirical equation for softening of clay was proposed by regression analysis method. The equation was imported into FEM program through compiled subroutine. Dynamic response of unreinforced and geogrid reinforced pavements was studied by FEM in order to investigate mechanisms of reinforcement. The results indicated that softening behavior of clay had visible effect on the performance of unreinforced and reinforced pavements. Geogrid reinforcement can provide lateral confinement at the bottom of the base layer by improving interface shear resistance and improve stress distribution on subgrade layer. The effect of geogrid reinforcement was also shown to reduce surface deformation and nonuniform settlement.