Fracture mechanics of plate debonding: Validation against experiment: Fid-Bau Portal

Fracture mechanics of plate debonding: Validation against experiment

Achintha, M. / Burgoyne, C.J.

Research highlights ► Global-energy-balance-based Fracture Mechanics can predict FRP plate debonding. ► Strain energy can be calculated using a modified form of Branson’s equation. ► Fracture Energy of concrete depends on compressive strength and the aggregate type. ► Values for Fracture Energy can be assumed if not quoted. ► The predictions agree well with experimental results reported in the literature.

Abstract The debonding of FRP plates from concrete beams is not amenable to finite-element analysis; fracture mechanics, based on a global energy balance, offers a better alternative. An analytical model with energy calculations based on a revised version of Branson’s model (to take account of the reaction to the force in the FRP) has already been developed. This paper presents comparisons with a variety of experiments reported in the literature and shows that the model can correctly determine both the failure load and the failure mechanism. The paper shows that debonding often propagates in the concrete, just above the interface, and hence the failure load is dependent on the Mode I fracture energy of concrete. The method can also be used to determine when premature adhesive failure occurred prior to debonding within the concrete substrate.