Multiple Fracture of Beams Under Localized Impulsive Loading

The fracture patterns produced by localized impulsive loading on brittle beams and their dependence on the intensity and length of the load have been determined. Experiments were performed on effectively infinite beams loaded over a finite length with sheet explosive. The mechanisms, location, and time sequence of deformation and fracture were determined by posttest observation and by high-speed framing camera photographs. It was found experimentally that all fractures were initiated by bending stress and that the localized impulsive loading produced three different fracture patterns. The beam response was also predicted analytically by numerically integrating the characteristic equations of Timoshenko beam theory. It was found analytically that, depending on load length and intensity, a total of four fracture patterns, including the three observed experimentally, can be produced by localized impulsive loads.