Abstract: A series of experimental studies on the dynamic fracture behaviour of three point bend beam with off center edge crack under transverse implusive loading are presented with the help of dynamic caustics. The effects of the off center position of the prefabricated cracks on dynamic growth (i.e. the crack initiation, the mixed mode stress intensity factor of the crack tip, the crack speed and crack trajectory, etc.) are analysed. By means of dynamic photoelasticity, the interaction between the stress wave...