Application and accuracy of basis functions implemented in a patch-by-patch approximation of mixed-type finite element

Matsubara, Hitoshi; Yagawa, Genki

The present paper discusses the accuracy of patch-by-patch approximation of mixed-type finite element scheme. In the approximation, not only a displacement field for each element but also stress and strain fields for each patch are defined. In order to determine unknown parameters of stress/strain fields of a patch, the Hu-Washizu principle is employed. In this paper, the accuracy of the generalized finite element functions implemented in the proposed approximation is shown. Furthermore, to show the effectiveness of the approximation in the fracture mechanics that have singular stress fields, the approximation is applied to linear fracture problem.