FIRST AND 2ND-ORDER STRESS EXTRAPOLATION FOR MODE-I AND MODE-II EDGE CRACKS

The use of linear and second order stress extrapolation to obtain K-I and K-II in two-dimensional finite element models of a thick plate con taining an edge crack was examined. Three loading cases were studied, including classical Model and Mode II problems and a problem of tribol ogical contact. Linear extrapolation was observed to yield accurate pr edictions of KI iri cases of dominant Mode I loading. In Mode II situa tions, notably where the crack faces experienced compressive normal st resses, second order extrapolation was observed to improve estimates o f K-II. (C) 1997 Elsevier Science Ltd.