Evaluation of the mode I stress intensity factor for a square crack in 3D

An algorithm for the computation of mode I stress intensity factors of a sq uare crack together with an error estimate is presented. The algorithm is b ased on a hypersingular integral equation. The leading singular behavior of the crack opening displacement in the corners is taken into account. The m aximum value of the normalized stress intensity factor, F-max, is estimated to F-max = 0.7534 +/- 0.0002. Previous investigators have estimated this q uantity in the interval F-max = 0.725 to F-max = 0.756. (C) 2001 Elsevier S cience Ltd. All rights reserved.