Shakedown analysis of pavements under three-dimensional moving loads

In this paper, a static approach for shakedown of pavements under three-dimensional moving surface loads is developed by means of Melan's lower-bound shakedown theorem. The pavement material is modeled as a Mohr-Coulomb medium and the surface loads are in Hertz load distributions. A critical residual stress fi eld is conceived that fulfi ls the equilibrium condition. By searching for the maximum permissible load, of which the corresponding elastic stresses combined with the critical residual stresses satisfy the Mohr-Coulomb yield condition everywhere in the half-space, rigorous lower-bound shakedown limits are obtained. The results show that the lower-bound shakedown limits vary with frictional coeffi cient, soil friction angle and Poisson's ratio. The critical point that controls the shakedown limit lies at the depth at which the minimum larger root (one critical residual stress fi eld) reaches its peak value.