On thermomechanical stress analysis of adhesively bonded composite joints in presence of an interfacial void

This paper deals with analytical thermomechanical stress analysis of adhesively bonded composite joints in presence of a structural imperfection in the form of an interfacial void within the adhesive layer based on the full layerwise theory (FLWT). The joints are subjected to mechanical tension, uniform temperature change, or steady-state heat conduction. The proposed adhesive joint is divided into three distinct regions along its length and a large number of mathematical plies through its thickness. Three sets of fully coupled governing equilibrium equations are derived employing the principle of minimum total potential energy. The three-dimensional nonlinear interlaminar stress distributions along the bond-line in the interior region and near the edges are obtained. The results, showing fast convergence speed and quite agreement with the finite element method, reveal that the presence of such defect within the adhesive layer can increase the stress concentrations resulting in premature failure and debonding.