Analytical yield load solution for overmatched center cracked tension specimen

Analytical upper and lower yield load solutions for weld strength overmatch ed center cracked tension specimens are found. Analysis is based on a simpl e discontinuous kinematically admissible velocity field and statically admi ssible stress fields. It is shown that the upper bound depends on a single dimensionless parameter beta = (M - 1)(H/W)/(1 - a/W) which includes effect s of the mismatch ratio M = sigma(Yweld)/sigma(Ybase) and geometrical dimen sions (H/W and a/W) of the specimen. For the certain range of the mis-match ratio the lower bound depends on the same single parameter. In spite of th e simplicity of velocity and stress fields assumed, very good agreement wit h previously conducted numerical calculations has been found. Moreover, the lower bound solution found under the plane stress conditions and the upper bound solution found under the plane strain conditions have shown that rel ative differences between the bounds and the exact value of the yield load are small even for arbitrary three dimensional deformation and are comparab le with differences which result from the shape of yield surface, Furthermo re, comparison with experimental results are given and discussed. (C) 1999 Elsevier Science Ltd, All rights reserved.