WEIGHT-FUNCTIONS FROM FINITE-ELEMENT DISPLACEMENTS

The weight function method has been extensively used in fracture mecha nics for stress intensity factor determination. It was shown that, if a complete solution (the crack face displacement and the stress intens ity factor) to a crack problem for one loading system is known, then t he solution for the stress intensity factor for the same cracked confi guration, but with any other loading, may be obtained directly from th e known solution. Several procedures have been proposed, which use a s olution for the stress intensity factor available from handbooks. In t his paper, an approach based on the crack face displacements obtained from a finite element analysis is used. This procedure can be applied without knowing a previous solution for a certain loading. The method proves to be extremely efficient, and some results and generalisations for a pressurised cylindrical shell with an external straight axial c rack are presented. (C) 1998 Elsevier Science Ltd. All rights reserved .