摘要：The reinforced mechanism is proposed to describe the energy dissipation of chopped fiber peeling and pull-out as the crack grows. Then, a finite element model (FEM) is established to simulate the process of the interfacial crack growth for a double cantilever beam. The energy release rate is calculated by the virtual crack closure technique (VCCT). The nonlinear spring element is employed to account for bridging effect caused by the chopped fiber. In addition, the foam core composite sandwiches with and without reinforced chopped fiber are manufactured by using the vacuum assisted resin injection process. The experimental investigation is performed to determine the interfacial fracture toughness for the sandwich specimens. Furthermore, the typical numerical examples are performed to simulate the interfacial crack of composite sandwich beams. The influence of the energy dissipation on the interfacial toughness is also discussed. The experimental and numerical results indicate that the reinforced chopped fiber is an effective technique to improve the interfacial toughness of the sandwich composites.
