Effectivity of the Hybrid Fiber Reinforced Polymer in Strengthening of RC-Beams

Fiber Reinforced Polymer (FRP) has been used as one of the repair or strengthening materials for deteriorated concrete structures. However, the elastic properties of FRP materials cause a limitations on the ductility of the reinforced concrete structure. This research focuses on the study of the behavior of reinforced concrete beams strengthened using a hybrid Carbon-Glass Fiber Reinforced Plastic (Hybrid FRP). Hybrid FRP is a combination of two layers of FRP that have different elastic modulus, namely Glass Fiber and Carbon Fiber. The objective of using hybrid composites is to obtain a combined elastic mode behavior from two kind of fibers. Flexural testing of reinforced concrete beams with FRP hybrid reinforcement was carried out to study the flexural behavior and also the effectiveness of strengthening. The test material is a reinforced concrete beam with dimensions of 150 mm x 200 mm x 3300 mm. Two types of beams were prepared, namely control beams (BN) and beams with FRP Hybrid strengthening (BGC). The composition of the FRP hybrid was 100% of Glass fiber and 40% of Carbon fiber to the width of the beam. The test results show that the beam with FRP hybrid strengthening has a moment capacity of 12% higher than the control reinforced concrete beam (BN). The mode of failure of the BN beams was the crushing of the concrete that was initiated by yielding of the steel reinforcement. For BGC beams, failure mode was in the form of debonding of the hybrid FRP layer.