Klaas, Ottmar; Schröder, Jörg; Stein, Erwin; Miehe, Christian:

A regularized dual mixed element for plane elasticity implementation and performance of the BDM element

In: Computer Methods in Applied Mechanics and Engineering, Jg. 121 (1995) ; Nr. 1-4, S. 201-209
ISSN: 0045-7825
Zeitschriftenaufsatz / Fach: Bauwissenschaften
In the present work we consider aspects of the formulation and numerical implementation of the BDM-Element (Brezzi, Douglas, Marini [1985], Stenberg [1988]). 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 (Fraeijs de Veubeke [1975]) which implies an approximation of the work-conjugate rotation field. Conditions for stability checks and optimal convergence of this element have been pointed out by Stein & Rolfes [1990]. Within this paper we discuss in detail algorithmic aspects of the implementation and perform comparisons with respect to the approximation behaviour of the Q1-, Pian-Sumihara- and the recently developed Q1/E5-Element.