Modular analysis of assemblages of three-dimensional structures with unilateral contact conditions

Abstract

We present a modular approach which is well-suited to the analysis of real situations of assemblages of three-dimensional elastic structures. The CONTRAST approach (CONtact and ThRee-dimensional Assemblages in STatic) takes easily into account local nonlinearities due to contact or to specific technological components (rubber joints, strongly prestressed bolts or rivets, etc.). It is based on a decomposition of the assemblage into substructures and interfaces. They are both mechanical entities with their own unknowns and their own equations. Interfaces play a major role by modelling easily and precisely the local nonlinearities such as contact and friction. An iterative scheme, based on the LATIN method (LArge Time INcrement method), is used for the resolution and the global problems on the substructures (which are independent) are solved by a finite element (FE) method. The CONTRAST approach is thus based on both a parallel oriented strategy and formulation. This parallelism is, above all, used to introduce some modularity and flexibility in the description of the problems and to allow the use of incompatible meshes on the interfaces. This also gives a reduction of the numerical cost with regards to the classical finite element approaches. For contact and friction problems, comparisons with an industrial FE code are presented. The examples present the possibilities of the CONTRAST approach for industrial assembly situations and the first numerical results presenting incompatible meshes on the interfaces.