On the choice of local element frame for corotational triangular shell elements

In the context of corotational triangular shell elements, the objective of this paper is to show that for certain stability problems it is interesting to choose a local element frame invariant to the element node ordering. Two methods of obtaining such a local frame are presented. These two methods, already proposed by other authors, are reformulated. For the first one, based on the minimisation of local nodal displacements, it is shown that the iterative process can be avoided. Copyright (C) 2004 John Wiley Sons, Ltd.