A fictitious domain decomposition method for a nonlinear bonded structure

International audienceWe study a fictitious domain decomposition method for a nonlinearly bonded structure. Starting with a strongly convex unconstrained minimization problem, we introduce an interface unknown such that the displacement problems on each subdomain become uncoupled in the saddle-point equations. The interface unknown is eliminated and a Uzawa conjugate gradient domain decomposition method is derived from the saddle-point equations of the stabilized Lagrangian functional. To avoid interface fitted meshes we use a fictitious domain approach, inspired by XFEM, which consists in cutting the finite element basis functions around the interface. Some numerical experiments are proposed to illustrate the efficiency of the proposed method. (C) 2020 International Association for Mathematics and Computers in Simulation (IMACS)