UNILATERAL CONTACT, FRICTION AND RELATED INTERACTIONS IN CRACKS - THEDIRECT BOUNDARY INTEGRAL METHOD

The paper presents a theory for the study of cracks having a given geo metry by taking into account all types of actions of monotone type lik e unilateral contact and friction phenomena between the two crack side s. The arising problems are of a non-classical nature, due to the inte rface conditions expressed in terms of non-differentiable convex super potentials. The direct B.I.E.M. is extended appropriately in order to treat this type of problem. The developed method is illustrated by a n umerical example concerning the calculation of stress intensity factor s under the unilateral contact and friction interface conditions.