Residual stresses in double-lap joints

This work presents an analysis of the bonding stresses at the interfaces between the adhesive bond lines and the adherends of a symmetric double-lap joint, due to the temperature change distributed along the adhesive material after curing or manufacturing. The analysis considers linear elastic behavior and presupposes the forms of the kinematic fields. The formulation then follows variational principles and the interlaminar stresses are evaluated as Lagrange multipliers which are incorporated into the internal energy. Our theoretical and numerical results indicate that the most detrimental stresses arise at the free edges while the temperature change at those regions is lowest. This phenomenon can be explained as one of the edge effects.