Buckling of plates and shells using sub-space iteration

Synopsis

The purpose of this study has been to explore the use of super-parametric finite elements for the determination of buckling loads for plates and shells. For this, it was necessary to develop the geometric stiffnews matrix for the shell element. In addition to this, it was necessary to choose a numerical method for the solution of the large scale eigen value problem that arises from the formulation. The sub-space iteration method was chosen for its versatility in handling large scale problems, but it was found that the standard technique broke down because of the presence of positive and negative eigen values. The paper describes how the method was modified to overcome this problem. Results are given for comparative studies on the buckling loads of both plates and shells.