The works presented in this document deal with numerical design methods and mechanical analysis of the behaviour of complex assemblies of structures including connection conditions such as contact, friction, joints, adhesives, ... The proposed approach are based on a decomposition of the assembly into substructures (modeling the componants) and interfaces (modelling the connections). A powerfull resolution method is proposed and compared to more classical ones in the framework of finite element methods. Some interface models describing adhesively bonded joints are then presented. Two approaches are then proposed for taking into account the uncertainties on the parameter of the interface models (gaps, friction coefiicients, prestresses, stiffnesses, ...). The first one is based on a multi-resolution technique for the construction of response surfaces. The second one is based on the use of stochastic finite elements and allows a more complete description of uncertainties. Examples dealing with industrial applications are presented. They show clearly the interest of the proposed tools.
