A general sandwich-type model for adhesive joints with composite adherends

Efficient analyses of adhesive joints are very important for pre-dimensioning or optimization processes. In this work a new model for adhesive joints is presented that can be applied to various joint configurations, as e.g. single lap joints, T-joints, L-joints or reinforcement patches. This is done by means of a two-dimensional, plane-strain model of the overlap region of the adhesive joint that is loaded by arbitrary section forces and moments — a so called general sandwich-type model. To account for shear deformations of the adherends, First Order Shear Deformation Theory is used. Arbitrarily laminated adherends are considered including asymmetric laminates with bending-extension coupling. The model yields a shear and peel stress distribution in the thin adhesive layer that is constant over the thickness. The results are compared to Finite Element Analyses for several joint configurations and show good agreement. A closed-form analytical solution is given for the case of identical adherends without bending-extension coupling. The general solution can be obtained with very low numerical effort. To allow for a ready use of the present solution an efficient MATLAB implementation is provided as supplementary material to this paper.