FRCM Strengthening of Shear-Critical RC Beams

Abstract

This paper presents the results of an experimental study conducted to investigate the effectiveness of different types of fabric-reinforced cementitious matrix (FRCM) composite systems to strengthen shear critical reinforced concrete (RC) beams. Seven shear-critical RC beams were tested. The test variables included the strengthening material (glass FRCM or carbon FRCM) and the strengthening scheme (side bonded or u-wrapped). The test results revealed that FRCM strengthening is effective in enhancing the load-carrying capacity of shear-critical RC beams. The increase in load-carrying capacity of the FRCM-strengthened beams ranged between 19 and 105%. Both strengthening schemes (side bonded and u-wrapped) exhibited similar behavior, suggesting that the excellent bond of the FRCM to concrete may not require u-wrapped applications for anchorage. The experimental results were also compared with theoretical predictions according to fiber-reinforced polymer (FRP) design guidelines in North America with some modifications. The American Concrete Institute (ACI) predictions were in good correlation with experimental results, whereas the Canadian Standards Association (CSA) predictions were slightly unconservative.