Chloride diffusion analysis of reinforced concrete beam enhanced with externally bonded fibre reinforced polymer considering the presence of rebars and stirrups

Abstract

This paper aims to realize a full scale modelling of reinforced concrete (RC) beam enhanced by externally bonded fibre reinforced polymer (EBRFP), considering both longitudinal bars and stirrups. To this end, several previous revisions to Fick's second law of diffusion were incorporated to establish a revised diffusion model. During the modelling, the following factors were taken into account simultaneously: time-dependent diffusion coefficient, timedependent surface chloride ion content, chloride binding effect, material inhomogeneity and load effect. Then, the boundary conditions were properly changed to fit the enhancement behaviour. Later, the revised diffusion model was numerically solved by the FEA on Abaqus, aiming to reveal the effect of enhancement on chloride diffusion, the effect of longitudinal bars and stirrups on chloride diffusion, and the results and efficiencies of 2D and 3D models. Through the analysis of simulation results, the author drew the following conditions: First, the EBRFP enhancement led to an obvious decrease of chloride ion content, thus extending the initial time of rebar corrosion; Second, the longitudinal rebars greatly boosted the chloride ion content at the front faces of rebars, while the effect of stirrups can be neglected if the longitudinal rebars have been considered; Third, 2D model is more recommended than 3D model if the surface chloride ion content remains invariant along the RC beam.

Alkali-Activated Slag cement: Alternative Adhesives for CFRP Sheets Bonded to Concrete at Elevated Temperatures

“…Hence, the fireproof adhesives with no cement or reducing the cement content have become research hot spot recently. In this study, blast furnace slag was adopted as an alternative of cement to produce AASC, and the purpose is to develop a high-temperature-resistant inorganic matrix for RC enhanced by FRP [19][20][21][22].…”