Elastoplastic analysis of shells without any local iterative calculations by block Newton method

In this article, a pseudo-stress for local residual and an algebraically derived consistent tangent are applied to elastic-plastic boundary value problems of shells. The authors define a coupled problem of the weak form of the equilibrium equation for the overall structure and the constrained equations for stress state, which include the yield condition and the plane stress condition, at every material point. Since the pseudo-stress for the residuals of yield criterion and plane stress state is incorporated into the linearized weak form of the equilibrium equation, the proposed scheme does not have any local iterative calculations and enables us to decrease the residuals in the coupled boundary value problems simultaneously. Some numerical examples using shell elements demonstrate the validity and effectiveness of the procedures in complex situation with material and geometrical nonlinearities.