Investigation of the behaviour of flexible and ductile ECC link slab reinforced with FRP

Abstract In this paper, a flexible and ductile link slab used to eliminate the expansion joints in the bridge deck system was proposed and investigated through a comprehensive study, including material design and structural experimental investigation. This novel link slab utilises highly ductile Engineered Cementitious Composites (ECC) and non-corrosive Fibre Reinforced Polymer (FRP) reinforcement. At the first stage of this study, an experimental investigation was carried out to evaluate the influence of compositions on the mechanical behaviour of ECC materials, particularly emphasis on flexural behaviour. The test and analytical results established the feasibility of attaining a type of ECC composite material with high deflection capacity, multi-cracking behaviour and small crack width (0.05 mm), which is suitable for the application of link slab in bridge deck system. Thereafter, the proposed ECC material combined with FRP reinforcement was adopted to conduct link slab specimens in full scale bridge decks. All the test specimens were tested under monotonic repeated loading. The performance was described based on the load-deflection/moment-rotation response, strain development, cracking and energy absorption. The influence of FRP reinforcing materials on the link slab structural performance was presented and discussed. The significant enhancement of deflection capacity and crack-width control in ECC link slab reinforced with FRP bars suggests that the use of ductile ECC and non-corrosive FRP reinforcement can be effective in extending the service life of joint-free bridge deck system.