REHABILITATION OF HIGH STRENGTH REINFORCED CONCRETE CORBELS USING BASALT FIBER FABRIC

Abstract

This paper presents an experimental study on the mechanical behavior of damaged reinforced concrete corbels rehabilitated by Basalt Fiber Fabric (BFF). The main research aim of the study is to investigate the effectiveness of basalt fiber fabric on rehabilitation of reinforced concrete corbels, which were damaged because of elevated temperatures and overloading, by examining load restoring capacity and ductility. Totally nine corbels that had been damaged before were selected for the study. The initial failure of the corbels had been because of overloading after heating them to several temperature levels (250oC, 500oC, and 750oC). These corbels had been produced from high strength self-compacting concrete with one concrete class (80 MPa) and three different amounts of steel fiber ratios (0%, 0.5%, 1%). However, shear span value for all corbels is same (90 mm). Experimental results show that use of basalt fiber fabric on damaged corbels increases the load carrying capacity and ductility significantly as compared to the corresponding values of corbels before initial failure. Besides, the stiffness of the corbels after rehabilitation is same with the stiffness of them before initial failure. Moreover, all of the rehabilitated corbels failed because of de-bonding failure mode and no visible damage was observed on the fabric

Keywords

• corbels,high strength concrete,rehabilitation,basalt fiber fabric,epoxy

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