Investigation of the structural performance of reinforced concrete using fibre reinforces polylers

Abstract

Due to its resistance to corrosion, Fibre Reinforced Polymers (CFRP, GFRP and AFRP) have recently been introduced as a potential replacement for steel in many construction applications. With the incentive of overcoming the costly effects of corrosion, there has been considerable research work carried out especially within the last decade, to investigate the possibility of replacing steel witl1 CFRP or GFRP. Fibre Reinforced Polymers, (mostly CFRP) offer many advantages as compared to Steel reinforcement including high strength to weight ratio, excellent fatigue characteristics, corrosion resistance, electromagnetic neutrality, low axial coefficient of thermal expansion, and ease of handling due to its light weight. However FRP materials have their own limitations, representecl mostly in th<".ir linear elastic behaviour up to failure, their lower stiffness, and strain compared to that of steel, different techniques are required to guarantee a ductile behaviour of the structure, with CFRP particularly at failure. Having considered the advantages and disadvantages of CFRP in reinforced concrete, this study aims to investigate the structural performance in replacing steel reinforcement with CFRP and GFRP re-bars. This was done using the structural analysis and experimental testing of C30 concrete beams reinforced with CFRP, GFRP and Steel reinforcements respectively. This study also investigates the structural behaviour of CFRP reinforced elements with different concrete grades, and comparisons between C25, C30 and C35 concrete grades were done. Unfortunately all three CFRP reinforced concrete beams failed by reinforcement slippage, which means that comparison could not be done with an ideal type of failure as predicted, the ideal failure for CFRP beams being compressive failure. Unlike CFRP reinforced beams, GFRP and Steel reinforced beams failed as expected, and this gave the opportunity to draw further conclusions and evaluate the behaviour of the reinforcement at failure. Furthermore, the dissertation includes a comparative cost analysis between CFRP, GFRP and Steel reinforced structures.