Hybrid Finite Elements

Abstract

The hybrid stress method of finite elements as advocated by Pian and others is reviewed. Whereas variational methods are the most frequently used vehicle for formulating hybrid finite elements, the present communication approaches these techniques via the principle of virtual work. The desire to lend physical interpretation to the various matrices resulting from the hybrid techniques provides the motivation to view these techniques from the standpoint of virtual work. In addition, a hybrid strain technique is proposed. It has the apparent advantage over the hybrid stress technique in that discontinuous stress fields are admitted. Finally, simple examples are presented to demonstrate, in detail, some of the more common hybrid techniques.