A proposal for estimating bond capacity in externally bonded FRP to concrete

According to high interest in using FRP in strengthening structures in the recent decades many studies have been conducted to clarify the mechanism of the system. One of the most common forms of using FRP is externally bonded reinforcement (EBR) and the most critical part of this system is the bond between FRP composite and concrete as it plays a remarkable role to transfer stress between FRP and concrete. Many models have been proposed in the literature in order to predict the bond capacity. Most of the current models are based on regression to fit a mathematical expression to the available experimental data. However, the models differ greatly in the way they incorporate different parameters. In this study, eight models proposed by other researchers have been evaluated using 684 test data collected from open literature. The result of the evaluation indicates the low accuracy of the existing models. In the lack of the valid models, this paper aims at developing a simple, yet accurate, formulation for bond capacity. Taking into account the parameters affecting the FRP-concrete bond capacity, a model is proposed using multivariate regression analyses. The proposed model which is a simple equation is in good agreement with the experimental data and outperforms the existing models.

Keywords:

externally bonded reinforcement (EBR) , concrete , bond capacity , FRP ,