A note on times to fracture in solid Perspex spheres due to point explosive loading

The internal fracturing of a Perspex sphere due to a localised explosive loading on its surface has been investigated both analytically and experimentally. The locations and times of occurrence of the fractures are predictable from an analysis of stress wave reflection from the free surface based on the methods of geometrical acoustics. High-speed photography was used to measure and note the order in time at which the different fractures occurred.