Experiment on Static and Fatigue Performances of Assembled Concrete-steel Link in Assembled Composite Bridge Deck

Assembled bridge construction is a promising method for future bridge engineering. The steel-concrete composite bridge is highly accorded with the principle of assembled construction. Furthermore, the application of reactive powder concrete (RPC) provides additional opportunities and challenges for further optimization of this steel-concrete composite bridge design, i.e., reducing the self-weight and accelerating construction. In this study, a prefabricated composite bridge deck made of coarse aggregate RPC, which has high elastic modulus and high toughness, was developed. A new joint, called concrete-steel link (CSL) is proposed to connect the prefabricated composite bridge decks to reduce the self-weight, achieve satisfactory crack resistance performance, and realize fully assembled and accelerated construction. The structural performance-the characteristics of load-deflection relationship, ultimate bearing capacity, and fatigue performance-of the prefabricated bridge deck and the CSL were tested by the 4-point bending test. The results of the static tests show that this fabricated composite deck display high deformability, bending ability, and ductility. All the failure sections were located in the RPC panel, which indicates that the CSL has higher ultimate bearing capacity than the cast-in-place coarse aggregate RPC panel. By implementing the CSL, the initial cracking stress is higher than 9.0 MPa, and is located close to the coarse aggregate RPC stiffened plate. The fatigue tests show that the stress amplitude is low, and after 800 million cycles of harmonic loading, there is no fatigue fracture on the CSL. The stress amplitude of the weld seam is just 26.8 MPa. The prestress in CSL is the key factor for both the static and fatigue performances. © 2018, Editorial Department of China Journal of Highway and Transport. All right reserved.