This example is taken from  (page 245). A plate ( wide, long) is perforated at the center with a hole with radius . The plate is stretched in length direction by increasing the overall strain in time. The other two boundaries are free to deform. Because of symmetry, only a quarter needs to be modeled. A mesh with 48 linear quadrilateral elements is used
The Young's modulus , Poisson's ratio , the Von Mises yield stress and the strain hardening . Plane stress conditions hold. The plasticity influence is characterized by at the upper edge for . The elasto-plastic analysis gives for . A purely elastic calculation would have given .