Interface Fracture Models of Concrete Externally Reinforced by FRP Plates

Abstract

In this paper, the fracture models on FRP-concrete bonded interface are summarized and compared for concrete structures externally reinforced with FRP plates. The energy release rates of the unified model of bi-material interface fracture specimens under the transverse and moment loads by the rigid, semi-rigid, and flexible joint models are compared. The results show that the classical rigid joint model under-evaluates the compliance, and it thus predicts the approximate energy release rate of the specimen. The semi-rigid joint model also under-evaluates the compliance and energy release rate of the specimen. The flexible joint model introduces two interface compliance coefficients to describe the crack tip deformation under the shear stress and normal stress, and it thus improves the calculation accuracy of both the compliance and energy release rate.