Numerical shakedown and non-shakedown responses of a Tresca half-space to a three-dimensional moving load

Abstract

Flexible pavements may fail due to excessive rutting as a result of accumulative plastic deformation; otherwise, if the load is small enough, pavements may deform plastically in the first number of load cycles and then reach a stable state which is termed as ‘shakedown’. Recently some lower-bound and upper-bound solutions have been developed to directly determine the load limit (i.e. shakedown limit) below which an elastic-plastic half space can shake down. However, the actual responses of an elasticplastic half-space subjected to repeated moving loads were not well revealed. In the present study, repeated moving surface loads are applied to a three-dimensional finite element model established in ABAQUS to research on the development of stresses and strains in a Tresca half-space. Also, a numerical shakedown limit can be determined according to the yield condition of structure under a static load following a number of load passes. It is found the development of residual stresses induced by plastic strains plays a key role in helping the half-space to reach the shakedown state. Good agreements are also observed between numerical and theoretical solutions for both shakedown limit and residual stress fields