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

We present a modular approach which is well-suited to the analysis of real situations of assemblages of three-dimensional elastic structures. The CONT RAST approach (CONtact and ThRee-dimensional Assemblages in STatic) takes e asily into account local nonlinearities due to contact or to specific techn ological components (rubber joints, strongly prestressed bolts or rivets, e tc.). It is based on a decomposition of the assemblage into substructures a nd interfaces. They are both mechanical entities with their own unknowns an d their own equations. Interfaces play a major role by modelling easily and precisely the local nonlinearities such as contact and friction. An iterat ive scheme, based on the LATIN method (LArge Time INcrement method), is use d for the resolution and the global problems on the substructures (which ar e independent) are solved by a finite element (FE) method. The CONTRAST app roach is thus based on both a parallel oriented strategy and formulation. T his parallelism is, above all, used to introduce some modularity and flexib ility in the description of the problems and to allow the use of incompatib le meshes on the interfaces. This also gives a reduction of the numerical c ost with regards to the classical finite element approaches. For contact an d friction problems, comparisons with an industrial FE code are presented. The examples present the possibilities of the CONTRAST approach for industr ial assembly situations and the first numerical results presenting incompat ible meshes on the interfaces. (C) 1999 Published by Elsevier Science Ltd, All rights reserved.