Finite element analysis of elastic-plastic plane contact problem with nonlinear interface compliance

A solution to the two-dimensional elastic-plastic contact problem taking into account the deformation of the surface roughness at the contact sone is presented. The problem has been described using an incremental variational functional followed by the approximation typical of the element displacement method. A special contact element composed of three discrete spring elements has been used for the simulation of nonlinear properties on the contact surface. The stiffness of these spring elements has been determined on the basis of some empirical mechanical characteristics of the contact flexibility of rough surfaces. The correctness of the algorithm presented has been illustrated by a computational example. The influence of parameters defining the contact compliance on the distribution of stresses and displacements on the contact surface is discussed.