ANALYTICAL SOLUTIONS OF REDUCED RIGIDITY PLASTIC BIFURCATION OF CIRCULAR PLATES

Two analytical solutions of reduced rigidity plastic bifurcations, res pectively for simply supported and clamped circular plates, are found in the way of a post-confirmed presumption for the distribution of unl oading area at the bifurcation. The J2 flow theory is used. While the solutions, by their bifurcation modes and distributions of the unloadi ng areas, recall many aspects of Engesser bifurcation, the correspondi ng bifurcation loads he above the true Engesser loads.