Experimental study on crack curving propagation in bending beams under impulsive load

Dynamic fracture behaviour of crack curving in bent beams has been investig ated. In order to understand the propagation mechanism of such cracks under impact, an experimental method is used that combines dynamic photoelastici ty with dynamic caustics to study the interaction of the flexural waves and the crack. From the state change of the transient stresses in polymer spec imen, the curving fracture in the impulsively loaded beams is analyzed. The dynamic responses of crack tips are evaluated by the stress intensity fact ors for the cracks running in varying curvature paths under bending stress wave.