Effect of residual stresses on the linear-elastic K_I–T field for circumferential surface flaws in pipes

摘要

This paper describes the effect of four realistic residual stress patterns on the crack-front constraints for circumferential surface flaws in the wall of a pipe, characterized by the linear-elastic K_I–T stresses. The numerical representation of the residual stresses combines a thermal-induced eigenstrain field with a local mechanical traction applied over the interface between the heat affected zone and the remaining pipe. The verification study confirms the accuracy of this approach based on the analytical K_I solution for a 2-D crack under prescribed residual stresses. This study demonstrates low crack-front constraints near the deepest crack front for three typical residual stresses.