A regularized dual mixed element for plane elasticity. Implementation and performance of the BDM element
We consider aspects of the formulation and numerical implementation of the BDM element. This element is based on an extended dual Hellinger-Reissner principle which leads to optimal convergence rates for the stresses and displacements. The element is characterized by a non-symmetric approximation of the stress field, which implies an approximation of the work-conjugate rotation field, by adding the couple equilibrium with a Lagrangian multiplier. We discuss in detail algorithmic aspects of the implementation and give comparisons with respect to the approximation behaviour of the Q1, Pian-Sumihara and the recently developed Q1/E5 element.
scientific article; zbMATH DE number 881073