Improved hybrid‐stress axisymmetric elements includng behaviour for nearly incompressible materials

A series of 4-node axisymmetric solid-of-revolution elements with quadrilateral cross-section are developed based on the hybrid-stress finite element model. The displacement interpolation is identical, and the elements differ in the stress field chosen; alternative schemes for selection of stress distribution are investigated. The performance of these elements is assessed and compared for the example problems of a thick cylinder and thick sphere under internal pressure. Of particular importance are convergence, intra-element stress distributions, and element performance as the incompressible state is approached.