Two Triangular Membrane Elements Based on Strain

The strain formulation approach improves accuracy and removes complications, such as shear parasitic errors and sensitivity to mesh distortions. For analyzing plane stress and strain problems, two new strain-based triangular elements are proposed. Both compatibility and equilibrium conditions are imposed to these elements. Contrary to the quadrilateral shape, triangular element facilitates proper meshing of various geometries. To formulate these elements, the linear strain field is assumed. The first element is a five-node triangular element, in which each node has two degrees of freedom. In the second one, which is a four-node element, drilling degrees of freedom are added to improve applicability of the element for bending problems. Various numerical examples and patch tests verify high accuracy and efficiency of the suggested elements in comparison with the other existing plane elements.