Dynamic pulse buckling of cylindrical shells under transient lateralpressures.

A theory of dynamic pulse buckling is developed for cylindrical shells subjected to symmetric lateral pressure pulses of duration ranging from an ideal impulse to durations so long that the pulse is a step load. To cover this range three theoretical models are used: a tangent modulus model for impulsive loads that produce plastic flow buckling, a strain reversal model for loads of intermediate duration which produce complicated elastic-plastic buckling, and an elastic model for long loads that produce elastic buckling. Peak pressure and impulse are identified as the most significant load parameters and critical curves for buckling are generated in the pressure-impulse plane based on an amplification of shell imperfections. It is shown that these curves, from the symmetric load theory, can be used to give reasonable estimates fbr criticalloads for snioothly Tarying asyninietric loads, such as from a lateral blast wave. Simple formulas are given for the critical curves in terms of the shell elastic and plastic material properties, radius-to-thickness ratio, and length-to-diameter ratio. The curves agree well with experimental results over the entire range of pressure and impulse.