THREE-DIMENSIONAL, FINITE-ELEMENT SIMULATION OF PERMANENT DEFORMATIONS IN FLEXIBLE PAVEMENT SYSTEMS

A methodology for obtaining a three-dimensional finite-element solution to the problem of a moving load on an elastic-plastic half-space is presented. The problem is particularly suited to an analysis of flexible pavement systems. The basis of the model is the following set of assumptions: (a) the material is homogeneous and infinite in extent in every horizontal plane; (b) the load is moving at a constant velocity; (c) the system is at steady state; and (d) inertial effects are neglected. A model problem was examined that consisted of a homogeneous half-space of an isotropic material obeying the von Mises yield criterion and the associated flow rule. The magnitude of the permanent deformations is calculated versus the value of the applied surface pressure. The residual stress field remaining after the passing of the load is also obtained. More general problems are solvable with the current version of the code. Extensions are discussed.