Shaking table test study on seismic performance of segmental- assembled self-centering concrete-filled steel tube single-span bridge

As a form of prefabricated structure, prefabricated segmental bridges can shorten construction time, reduce traffic delays, improve construction quality control, and minimize the impact on the environment. At present, certain studies have been conducted on the seismic performance of such bridge piers under pseudo-static forces, but there are few studies on the mechanical performance of such piers or bridge structures under anticipated strong earthquakes or under deep water conditions. A segmentally-assembled self-centering concrete-filled steel tubular (PSCFST) bridge pier with external energy-dissipation steel bars was proposed, and underwater shaking table tests on a quarter-scale single-span bridge using PSCFST piers were carried out. The impact of hydrodynamic pressure on the seismic performance of PSCFST bridges was studied. The bridge was subjected to unidirectional ground motions at different peak levels. Considering the working conditions of four water depths (i.e., no water, 1.2 m, 1.5 m and 1.8 m), the superstructure response of the PSCFST bridge specimen under different water depths was compared. The experimental research shows that the PSCFST bridge has good seismic performance, there is no obvious damage to superstructure and substructure. As the water depth increases, the damping ratio of the PSCFST bridge increases, the natural vibration period decreases, the acceleration response of the superstructure decreases, and the displacement response does not change significantly. © 2021, Editorial Office of Journal of Building Structures. All right reserved.