A comparison of triangle and quadrangle finite elements for large strain elastoplastic formulations

The paper presents a comparative study of different elastoplastic large strain formulations used in research groups in Mendoza and Li`ege. The comparison is focused on a few academic standardized problems, in particular necking of a cylindrical bar in tension. Stress distribution at necking section, as well as load histories are analyzed for all three formulations. Two other test cases consider bending of the so-called ”Greco” beam and upsetting of a cylinder. Numerical results show that all approaches yield very similar results and thus are equally valid. Furthermore, quadratic 6-noded triangles provide a good alternative to bilinear quadrangles, even if sometimes they appear to be
more sensitive to big distorsions.