An improved adaptive formulation for the computation of limit analysis problems of thin axisymmetrical shells

An improved adaptive technique for the finite element formulation of limit analysis problems of symmetrically loaded thin shells of revolution is presented. Bending, membrane behavior and changes of curvature are simulated by using an axisymmetrical thin shell element of three nodes associated with a new piecewise linear (PWL) yield surface. The results obtained show better upper bounds when compared to other numerical and analytical solutions reported in the literature. Finally, an a posteriori error measure is re-written to include the new displacement rate and PWL strain rate fields, resulting in an adaptive scheme for refining the finite element mesh.