Dynamic effects in crack bridging

Problems in the mechanics of fiber bridging under dynamic conditions are solved theoretically using shear lag approximations and FEM. Various aspects are investigated further using experiments on model material systems. Special attention is paid to the problem of dynamic fiber pullout and push-in, which has been central to understanding fracture in aligned fiber composites under static conditions. Highlights for the dynamic problem are that: 1) inertia complicates the fiber pullout problem considerably; 2) disturbances propagate along frictionally coupled fibers at less than the bar wave speed; and 3) unstable regimes appear in interfacial friction.