LORA—an accurate four node stress plate bending element

A simple and accurate four-node quadrilateral plate-bending element based on stress assumptions is presented. Initial theremal strains and transverse shear stresses are included. The derivation is straightforward and without gimmicks and no numerical integration is necessary. The element behaves well for a wide range of aspect ratios with excellent convergence characteristics. The element is now being used in a practical warped configuration and with anisotropic material properties in the Lockheed-California Company NASTRAN system.