A NUMERICAL MODE-I WEIGHT FUNCTION FOR CALCULATING STRESS INTENSITY FACTORS OF 3-DIMENSIONAL CRACKED BODIES

A numerical mode I weight function first presented by Parks and Kamene tzky [1] is extended for application to three-dimensional cracked bodi es. This weight function makes use of the stiffness derivative method as part of finite element calculations. A virtual crack extension is e mployed. The major difficulty is proper interpretation of the shape fu nction variation for implementation in three dimensions. Numerical exa mples in two and three dimensions are examined. Excellent results are obtained in comparison to solutions in the literature, as well as some further finite element studies which are carried out here.