Properties of frictional bridging in fiber pull-out for fiber-reinforced composites

Stress equilibrium equations, boundary- and continuity-conditions were used to establish a theoretical model of progressive debonding with friction at the debonded interface. On a basis of the minimum complementary energy principle, an expression for the energy release rate G was derived to explore the interfacial fracture properties. An interfacial debonding criterion G≥Гi was introduced to determine the critical debond length and the bridging law. Numerical calculation results for fiber-reinforced composite SCS-6/Ti-6Al-4V were compared with those obtained by using the shear-lag models.