A Study of Elastic-Plastic Analysis by the Assumed-Stress Hybrid Finite-Element Model, with Application to Thick Shells of Revolution.

Two numerical methods have been developed, using the assumed-stress hybrid finite-element model as a basis, for the elastic-plastic, small deflection analysis of structures under static loading. The two approaches chosen the initial-strain approach and the initial stress-approach, result in a set of linear incremental simultaneous algebraic equations to be solved for each increment in applied external loading, with the global stiffness matrix remaining unchanged throughout the loading process and the effects of plasticity included as equivalent loading.