Stability of the enhanced assumed strain finite element method

The basic theory of the Enhanced Assumed Strain Modes (EASM) and the corresponding constitutive relationship as well as finite element formulation were addressed. In order to overcome the deficiency of the original method proposed by Simo, i.e., the Hourglass modes appear in the case of compression, algorithms for updating stresses and interior variables were developed by using an optimal post-process technique. It were proved from numerical results that the improved EASM is of good stability especially in the case of large compressive situation being involved.