Experimental Study on Shear Strengthening of RC Beams with an FRP Grid-PCM Reinforcement Layer

Abstract

This paper investigates the shear strengthening effect of a number of reinforced concrete (RC) beams strengthened by a reinforcement layer which combines carbon fiber reinforced polymer (CFRP) grid and polymer cement mortar (PCM). A total of ten RC beams, including three types of specimens as Series A and seven kinds of specimens as Series B, were prepared and investigated. The test variables in both series of experiments included various reinforcement ranges and different reinforcement amounts that consisted of CFRP grids’ spacing and cross-section areas. The experimental results suggest that the shear strengthening effect of the CFRP grid-PCM layer for RC beams is obvious and adequate. Meanwhile, better performance is observed if the CFRP grid-PCM reinforcement layer is used for the full sectional reinforcement of RC beams with an I-shaped profile, in contrast to RC beams with reinforcement of the web only. In addition, a new evaluation method based on the effective strain of the CFRP grid is developed to determine the shear capacity of RC beams strengthened by a CFRP grid-PCM layer.