Experimental Study on Prestressed CFRP-reinforced Aluminum Alloy Bridge Panel Based on Shape Memory Alloys

In order to strengthen aluminum alloy bridge panels, a CFRP (Carbon Fibre Reinforced Plastics) plate is tensioned under the bottom plate to exert prestress. Installing the tensioning device under narrow bottom plates of bridge panels via traditional prestressing method is difficult; therefore, a new prestress tensioning technology based on Shape Memory Alloy (SMA) is employed to efficiently apply the prestress. The tensioning and anchorage device used in prestressing technology has been designed and manufactured. A tensile stress of 360Mpa was applied to the CFRP plate with the tensioning and anchorage device and then, load-bearing tests were performed on prestressed reinforced aluminum alloy and unreinforced bridge panels, respectively. Experimental results showed that the proposed CFRP prestressing technology was feasible and verified the application possibility of SMA as a prestress device in practical engineering. The new technology ensured that the desired prestress value was applied to aluminum alloy bridge panel and the strength and stiffness of aluminum alloy bridge panels reinforced with the proposed technology were significantly improved.