Stress waves in solids

The aim of this paper is to discuss, in fairly elementary fashion, the topic of the transmission of transient stress pulses of short duration in solids, together with the associated problem of the measurement of pressures subject to very rapid changes. The pressure bar method, devised by Betram Hopkinson, forms one of the basic experiments in the field and it is described in some detail. An analysis of the limitations of the method leads to a discussion of the change of form of stress wave pulses as they recede from the origin, and the main features of the distortion are discussed when the pulses are propagated in (a) elastic solids, (b) visco-elastic solids, and (c) solids stressed beyond the elastic limit.