STRENGTHENING OF REINFORCED CONCRETE BEAMS WITH STEEL REINFORCEMENTS BY NSM SYSTEM

Abstract

To enhance the service loading requirement, imposed cyclic loading and errors in design, reinforces the re-construction of existing structural members to improve its strength. In the current scenario, two primary methods of strengthening were in usage which shows remarkable results. Active strengthening systems are EBR (Externally Bonded Reinforcement system) and NSM (Near Surface Mounted system). In this study, an experimental investigation was made for strengthening of reinforced RC beams in flexural behavior with NSM systems employing various proportions of steel bars. Beams were tested with two-point load test setup up to failure, on 4 RC beams of size 125 mm width, 200 mm depth and 1800 mm length which are strengthened with varied combinations of steel reinforcement. Yield strength and ultimate strengths of RC beams, failure modes, ductility behavior and cracking behavior was recorded and reviewed based on measured load and deflection. The final output of this project results in increasing of deflection, ductility nature and also flexural strength raised up to 54.82%.