ANALYSIS OF BONDING PROBLEMS UNDER THERMAL LOADING USING THE COMBINED MIXED FUNCTIONAL

Abstract

A new mixed model based on the combined mixed functional has been developed for the analysis of problems with bonding conditions and applied to the bimetallic thermostat problem. The mixed formulation has satisfied equilibrium equations, the displacement and the traction boundary conditions, as well as the interfacial continuities of traction in an average sense by virtue of the variational condition of the proposed mixed functional. A mixed finite element (QC 4/8), having no stability problem, has been proposed and successfully applied for the analysis of bonded structures with the selected combination coefficient. A bonding element has been developed based on a patch test-passed quadratic approximation for the relative displacements and bonding tractions in an average sense. Along all the bonding interfaces the results of the mixed method with the continuous stress interpolation were in close agreement with those of the stress formulation based on the principle of complementary virtual work.