Elasto-plastic analysis of anisotropic plates and shells by the least squares collocation method

This paper extends the use of the Least-squares collocation method to elasto-plastic analysis of anisotropic thin plates and doubly-curved shallow shells. The problem formulation is based on equilibrium equations, in which the plastic deformation is taken as an effective plastic load. The doubly fifth B-spline functions are used as the displacement trial functions, and both perfectly plastic and strain hardening behavior are considered .The yield function is generalized by introducing anisotropic parameters of plasticity which are updated during the material strain hardening history. Numerical examples are given and the present solutions, which are in close agreement with the available results obtained by the Hnite element method, demonstrate the simplicity, accuracy and efficiency of the present method.