Mechanical and durability properties of fiber reinforced concrete overlay: Experimental results and numerical simulation

Abstract Nowadays, fiber reinforced concrete (FRC) overlays are used for repairing and reinforcing pavements. In this research, some experimental tests performed to investigate the effects of steel and synthetic fibers on the performance of the concrete overlay. The synthetic fiber in this study is based on Modified Synthetic Polypropylene (MSP) Fiber. Plain and FRC specimens underwent flexural and compressive strength, and durability tests. The results show that the use of MSP in concrete overlays increases compressive and flexural strength, residual strength, ductility, and energy absorption, and reduces the resistance of concrete against freezing and thawing cycles. Using similar addition volume, Steel Fiber Reinforced Concrete (SFRC) has better flexural performance and lower compressive strength and workability than Modified Synthetic Polypropylene Fiber Reinforced Concrete (MSPFRC). To determine the thickness of the bonded concrete overlay (t), the Portland Cement Association (PCA) design criteria were used. In this study, these criteria simulated using finite element (FE). The results showed that the use of MSP in concrete overlays could reduce the thickness of bonded concrete overlay up to 15%.