Dynamic failure analysis of bimaterial beam with crack tip terminating interface

The experimental methods of dynamic photoelasticity, optical caustics and the numerical method of finite element technique are utilized to study the transient response and the debonding failure of a cantilever beam of bimaterial with an edge crack in the center part of the main beam terminating at the interface with the reinforced beam. The isochromatic patterns are observed to investigate the bending wave propagation of elastodynamic stresses in the composite beam and the shadow patterns of optical caustics are recorded to obtain the response of the dynamic stress intensity factors of the crack tip in the main beam to illustrate the effect of the reinforcement. The stress distribution at the interface is analyzed to interpret the bond rupture of the adhesive layer of the composite structure. The experimental results and the numerical analysis show clearly the dynamic behavior of the composite beam before and after the interface debonding.