Abstract
In finite element analysis, a kind of instability, which is called the hourglass mode, arises when one-point quadrature integration rule is used to calculate the stiffness matrix for the 2-D quadrilateral element. To control the instability, various kinds of methods have been proposed, among them, the one proposed by Kosloff and Frazier is thought to be the most effective and simple one, but in their paper, they confined the hourglass control method within the elastic problems. In this paper, the details of how to apply the hourglass control method in nonlinear analysis is presented, and a modified scheme is proposed to obtain the accurate nonlinear element response.
