Abstract :
The natural approach of finite element method initiated by Argyris is a efficient method, especially for nonlinear analysis of plates and shells, it gives simple formulations for stiffness matrix and geometrical stiffness matrix so that its implementation on computer is also simple. In this paper, we give another procedure for derivation of the geometrical stiffness matrix. The procedure is suited to the natural approach and the geometrical stiffness matrix given by this procedure is simpler as well as consistent. A lot of examples in this paper illustrate the comparison of this derivation procedure with the original method and show that the new procedure gives almost the same results as those given by the original one in most cases, while it can fill up some shortages of the original one, so that it gives another possible way for deriving geometric stiffness matrix with natural approach.
