Analysis of Adhesive-Bonded Joints, Square-End, and Spew-Fillet—High-Order Theory Approach

Abstract

The analysis of adhesive-bonded joints using a closed-form high-order theory (CFHO theory) is presented, and its capabilities are demonstrated numerically for the case of single lap joints with and without a “spew-fillet.” The governing equations based on the CFHO theory are presented along with the appropriate boundary/continuity conditions at the free edges. The joints consist of two metallic or composite laminated adherends that are interconnected through equilibrium and compatibility requirements by a 2D linear elastic adhesive layer. The CFHO theory predicts that the distributions of the displacements through the thickness of the adhesive layer are nonlinear in general (high-order effects) and are a result of not presumed displacement patterns. The spew-fillet is modeled through an equivalent tensile bar, which enables quantification of the effects of the spew-fillet size on the stress fields. Satisfactory comparisons with two-parameter elastic foundation solution (Goland-Reissner type) results and finite-element results are presented.