Saturated impulse for pulse-loaded elastic-plastic square plates

This paper investigates the phenomenon of saturated impulse in elastic-plastic plates whilst a fully clamped square plate is taken as a typical example, and the correlation is made between the saturated impulse obtained from the elastic-plastic analysis and that predicted by the rigid-plastic approximation. The present analysis suggests that two saturated impulses can be defined for an elastic, perfectly plastic structure: one is for the maximum deformation and the other is for the permanent (final) deformation of the structure. In general, the former is smaller than the latter. For the clamped square plates calculated, these two saturated impulses in the high load range lie between the upper and the lower bounds of the saturated impulse obtained from a rigid, perfectly plastic analysis; and finally, a `'saturated duration'' for loading pulse (critical pulse length) is proposed. (C) 1997 Elsevier Science Ltd