Simplified stress resultants plasticity on a geometrically nonlinear constant stress shell element

The geometrically nonlinear constant stress triangle of Morley is implement ed and extended to include material nonlinearity. The facet element was des igned in a total Lagrangian approach and is valid for moderate rotations. I n a search for a simple plasticity formulation, stress resultants plasticit y (involving a solution of single scalar yield function) is employed. A mod ification is introduced in the Ilyushin yield surface such that it is rende red a hyperellipse to avoid corner discontinuities, Explicit plasticity equ ations are derived so as to avoid the most involving matrix operations and attain faster computations. In this work it is aimed to study the performan ce of the element and assess its application to practical problems such as plate buckling in offshore structures. The formulation appears to work well . (C) 2001 Elsevier Science Ltd. All rights reserved.