Limit analysis of structures: A convex hull formulation

Limit analysis is treated herein in the framework of mathematical programming introducing a convex hull formulation for expressing the yield conditions in static and kinematic theorem. The proposed formulation differs in the number of variables and yield constraints compared to the standard one, which expresses yield condition as the intersection of halfspaces The two formulations are compared in terms of computational efficiency. Numerical results of plane steel frames prove the computational advantages of convex hull formulation for both 2D and 3D stress resultant interaction and demonstrate the effect of combined stresses on the load carrying capacity. (C) 2015 Elsevier Ltd. All rights reserved.