a new higher-order strain-based plane element

A new higherorder triangular plane element with drilling degrees of freedom is proposed by assumption of secondorder strain field. in addition to inclusion of drilling degrees of freedom and utilization of higherorder assumes strains, satisfaction of equilibrium equations improves performance of the suggested element in comparison with many of the other available elements. after proposition of the new element, a series of benchmark problems are solved to evaluate performance of the suggested element. accuracy and efficiency of the suggested element is compared with other strainbased plane elements. detailed discussions are offered after each benchmark problem. finally, based on the attained results, a final conclusion about characteristics of robust membrane elements is made.