Crack-arresting and Strengthening Mechanism of Hybrid Fiber Reinforced Polymer Sheets in Strengthening of Reinforced Concrete Beams

The failure process of reinforced concrete (RC) beams is exactly the emergence and propagation process of cracks. According to the principles of Fracture Mechanics, if the cracks were retarded in RC beams, the structure performance would be improved. In this paper, hybrid fiber reinforced polymer (HFRP) sheets are proposed to retard crack propagation in RC beams, and the crack-arresting and strengthening mechanism of the HFRP composite in the strengthening of RC beams is revealed, which is substantiated by the finite-element-modelling (FEM) analysis and bending improvement of RC beams with externally-bonded hybrid glass/carbon FRP (Hybrid G/C FRP) sheets.