A plane hybrid element with rotational d.o.f. and adjustable stiffness

Abstract

Abstract A simple formulation of a nine d.o.f plane triangle is achieved by the assumed‐stress hybrid approach. The element has two translations and the rotation about a normal to the plane as d.o.f. at each node. Performance of the element is shown to be good. A device for softening overly‐stiff elements is found to be effective and is suggested as a widely applicable method of improving the behaviour of hybrid elements. A particularly simple form of the element, herein called the CST Hybrid, appears to be the best performer.