A 3-D 6-NODED FINITE-ELEMENT CONTAINING A LAMBDA-SINGULARITY

A three-dimensional six-noded prism (wedge) finite element containing a singularity of order lambda is developed. The interpolation function s of the displacement allow for variations proportional to the power l ambda of the distance from the crack front along the crack surface and to the distance in the perpendicular direction. The element is compat ible with standard wedge (6-noded) and brick (8-noded) isoparametric e lements. Three problems are studied to examine the proposed element, n amely, a penny-shaped crack in a cylinder, an edge crack in an homogen eous material, and a crack perpendicular to a bimaterial interface.