A State-of-the-Art Review: Side Near Surface Mounted (SNSM) Technique for Strengthening of RC Beams

Abstract

Near surface mounted (NSM) technique with fiber reinforced polymer (FRP) worldwide is the most repairing systems for existing concrete structures. The use of NSM strengthening technique to RC members is an alternative method used for applying FRP flexural strengthening. Some limitations of applying the NSM to RC members such as; minimum value of groove to NSM bar diameter and minimum net distance between groove and the beam edge and between two adjacent grooves, which limits the use of NSM technique in RC beams with limited width, therefore many researcher introduce side near surface mounted (SNSM) technique by placing the FRP grooves at the sides of the beam. SNSM technique produced a significant enhancement in the flexural capacity of the RC beams. This paper reviews current research on RC members strengthening with SNSM technique. It focuses on the effect of NSM strengthening bar length, strengthening materials type, strengthening diameter, effect of filling material, effect of end anchorage, strengthening position, effect of spacing between NSM bars, prestress level of FRP, longitudinal reinforcement ratio and effect of pre-cracking of strengthened beams.