THE DEFORMATION AND TEARING OF THIN CIRCULAR PLATES SUBJECTED TO IMPULSIVE LOADS

This investigation examines the failure of circular plates subjected to impulsive velocities. Experiments are conducted on fully clamped circular mild steel plates subjected to a uniformly distributed impulse. The strain rate-sensitive plates exhibit mode I (large ductile deformation), modes II (tensile-tearing and deformation) and mode III (transverse shear) failure modes. An energy analysis is used on the test results which enables an energy balance equation relating input, deformation, tearing and disc energies to be formulated. The input and disc energies are obtained from experimental measurements; the deformation energy is predicted by making use of the final deformed height, a shape function and a rigid-plastic analysis. Good correlation is found and the experiments show good repeatability. The threshold velocities for the onset of failure modes II and III are given.