A weight function for the crack surface tractions in chevron-notched specimens

A numerical solution is obtained for the weight function of the crack surface tractions in a chevron-notched specimen using finite element analysis. The finite element idealization of the quarter sample composes of 9368 nodes, 2012 quadratic isoparametric elements and about 28100 degrees of freedom. The stress intensity factor at the tip of a crack in a chevron-notched specimen is calculated for the direct line loading of the crack surfaces by a constant traction. The traction is applied at different positions between the apex of the chevron notch and the crack tip. The value of the weight function, h, at the position x and for the crack length a is then calculated from h(xa) = K(a)/P/b(x), where K is the stress intensity at the crack tip, P is the magnitude of the tractions and b(x) is the local width of the wake where the traction P is applied. A polynomial similar to that of the weight function for the edge-crack plate is fitted to numerical results. (C) 1998 Elsevier Science Ltd. All rights reserved.