Multiple run-arrest phenomena in brittle fracture

ABSTRACT A special class of transient crack propagation problems arise from the interaction of stress waves with a rapidly moving crack. We study an extreme case in this class; namely, the repeated occurrence of sudden acceleration and intermittent crack arrests within a single test specimen. Using novel optical techniques, we have obtained real-time continuous measurements of the stress intensity factor and instantaneous crack-tip velocity during a series of run-arrest segments in brittle polymeric beams. Such observations provide new insights into the role of inertia effects in bending fracture.