Sensitivities of Interfacial Bond-Sip Properties in Predicting the Behaviour of FRP-Strengthened Concrete

The performance of FRP-bonded concrete is heavily influenced by the properties of the bond between the two materials. Various bond-slip models incorporating interfacial bond properties have been developed to understand and predict this behaviour. In a bond-slip model, the interfacial bond properties are specified in terms of the bond shear stress at the interface and the associated slip or interfacial fracture toughness (energy). Therefore, it is crucial to determine the sensitivity of these properties to the structural response, as it affects the prediction of FRP-bonded test samples and debonding failure modes. This study investigates the sensitivities of interfacial bond-slip properties using a bond-slip model comprising ascending and descending curves. The results indicate that the interfacial fracture energy significantly affects the maximum load resistance, while the ascending curve has a substantial impact on the effective bond length. These findings shed light on the importance of interfacial bond properties in determining the performance and behaviour of FRP-bonded concrete structures.