Failure Criteria for FRP Adhesive Lap Joints: A Comparative Analysis

In this paper the debonding of adhesive lap joints between FRP adherents is analyzed with regard to the influence of the chosen interface failure criterion. In particular, the results obtained by using the well-known criteria of Hutchinson and Suo, Xu and Needleman, and Camacho and Ortiz, are compared. Due to the mathematical formulation of such cohesive interface models, the examined mechanical problem is non linear, although the adherents are supposed to be linear elastic up to failure. Furthermore, shear deformability of the adherents is taken into account. The numerical results of a finite element analysis are presented and discussed. Suggestions for the design of adhesive lap joints are also given.