Behavior of strengthened reinforced concrete beams under different CFRP strips arrangement

摘要

The Carbon Fiber Reinforced Polymer (CFRP) composite is widely used as a strengthening solution for repairing civil engineering structures. The main objective of this paper is to investigate the effects of strips arrangement on the behavior of Strengthened Beams (SB) using the Near-Surface Mounted (NSM) and the Externally Bonded Reinforcement (EBR) techniques. The experimental program consists of five strengthened beams by different configurations of CFRP. The beams were tested under bending in four-point test. The experimental program comprises two beams strengthened by one and two strips according to the NSM technique. Two other beams were strengthened by the same configuration with the EBR technique, whereas the last beam was un-strengthened and considered as the Control Beam (CB). The behavior of the control and strengthened beams was compared. The effectiveness of different CFRP configurations was evaluated. The obtained results revealed that the crack patterns were affected by the strips arrangement. These results showed also that the flexural load capacity, the ductility and the strains of concrete, steel and CFRP strips were influenced by the arrangement of plates. This paper also highlighted the beams failure modes due to the different configurations of strengthening.