AN ANALYSIS OF COUPLING BETWEEN PLANE CRACKS AND CONTACTS

A numerical analysis is presented to discover if the change in complia nce of a half-plane, due to the presence of a flaw, has any significan t effect on the pressure distribution beneath a rigid, flat-ended inde nter sliding over the surface of the half-plane close to the defect. I t is shown that, when the indenter is constrained to remain vertical, the change in pressure distribution may be of sufficient magnitude to alter the stress intensity factors at the crack tip compared with the standard uncoupled approximation. However, this effect is only signifi cant when the coefficient of friction between the indenter and the hal f-plane takes values towards the upper end of those experienced in pra ctice, and when the geometry of the problem lies within a very small r ange. In most practical problems, therefore, the influence of coupling , as defined above, may be neglected.