SECONDARY BUCKLING OF CIRCULAR PLATES

It is shown by using a formal perturbation expansion, that unsymmetric equilibrium states branch from axisymmetric buckled states of the uniformly compressed and clamped circular plate. The process is called secondary buckling and the edge thrusts at which the branchings occur are called the secondary buckling loads. In the neighborhoods of the secondary buckling loads that are studied, the secondary states exist for thrusts less than the secondary buckling loads. The minimum secondkary buckling load is approximately 7. 5 times the primary buckling load of the plate. The linear boundary value problems that are obtained in the application of the perturbation method are solved numerically.