الفهرس 
SCOPE OF STRENGTHENING TECHNIQUES
External strengthening using steel platesOnly 14 pages are availabe for public view
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Abstract
Strengthening and rehabilitation of concrete structures using fiber reinforced polymers (FRP) has increased for the last three decades. FRP strengthening systems are widely used due to the development of several design guidelines and codes. FRP materials have the advantages of being light weight,noncorrosive, and high tensile strength to weight ratio in comparison to steel.However, when FRP strengthening systems are subjected to a combination of aggressive environmental and high temperatures; the epoxy used to bond FRP to concrete may soften and consequently lose its ability to transfer stresses from the substrate concrete to the strengthening fibers. This drawback led to the need to develop alternative adhesive for the external fibers strengthening systems.The objectives of this research is to investigate the use of mineral based composite mortar (MBC) as an alternative to epoxy adhesive for FRP strengthening systems. The experimental program included eight full-scale reinforced concrete beams strengthened in flexure using MBC, in addition to four beams that were initially pre-cracked and then repaired. The load carrying capacity, deflection, ductility, crack behavior and modes of failure for the strengthened beams were investigated to assess three major parameters. The parameters included evaluation of the efficiency of using MBC mortar as adhesive in comparison with epoxy, the effect of MBC mortar thickness, the effect of using different fiber reinforcement ratios and pre-loading level of repaired beams. The study was ended with analytical model to estimate the flexure capacity .Test results indicated that MBC can achieve relatively high increase in flexural capacity of the concrete beams compared to epoxy. The analytical model showed close agreement with the experimental results and was extended to produce design charts.