Stress intensity factor calibration for short cracks at the edge of semi-infinite contacts

An asymptotic representation of the sub surface stress field allows us to find crack tip stress intensity factors for cracks nucleating from the edge of incomplete contacts. For the asymptotic representation to be valid we require the cracks to be short compared to any other dimension characterising the contact. The general asymptotic formulation allows us to incorporate the results in different contact problems as long as the contact is incomplete. We show that, for the load cases considered, crack closure is not an issue as long as the mode ??????stress intensity factor is positive.