Lower bound limit analysis by the symmetric Galerkin boundary element method and the Complex method Original Research Article

A solution procedure for lower bound limit analysis is presented making use of the Symmetric Galerkin Boundary Element Method (SGBEM) rather than of finite element method. The self-equilibrium stress fields are expressed by linear combination of several basic self-equilibrium stress fields with parameters to be determined. These basic self-equilibrium stress fields are expressed as elastic responses of the body to imposed permanent strains obtained through elastic–plastic incremental analysis. The Complex method is used to solve nonlinear programming and determine the maximal load amplifier. The numerical results show that it is efficient and accurate to solve limit analysis problems by using the SGBEM and the Complex method.