An algorithm for plastic limit analysis Original Research Article

This paper introduces an algorithm for the limit analysis of perfectly plastic bodies. The algorithm is based on the finite element technique and mathematical programming. Using an ellipsoid yield surface, identical upper and lower bounds of the limit load can be determined for a discrete body. In the case of using a non-ellipsoid yield surface, an iteration procedure is suggested to obtain the limit load. In each iteration, the non-ellipsoid yield surface is approached by an ellipsoid at each point of the body. The parameters of the approximated ellipsoid are different at different body points and determined based on the previous iteration. Numerical examples are presented to demonstrate the validity of the present method.