Application of the Tangent-Stiffness Method in the Finite Element Modelling of the Behaviour of Interface Surfaces

Abstract

To simulate the behaviour of an interface formed between two contacting bodies using the finite element method, a review of previous approaches employed by other authors who worked with the same finite element method is carried out; their models and experimental data evaluated. A third-degree polynomial approximation approach is first undertaken  to model the behaviour of the interface during loading, unloading and reloading. An incremental method and an iterative procedure are both employed. Finally,  the tangent-stiffness method in which, for every iterative step, a portion of the external load is applied and the shear and normal stiffnesses are calculated is introduced. An example of a prismatic beam on a rigid base is analyzed and the predicted results are compared with those obtained from experiments.