Seismic performance of precast hollow concrete bridge double columns with shallow socket connection

Abstract

In this paper, a precast hollow concrete bridge double column with shallow socket connection (PHCBDCSS) is proposed for reducing the socket depth and achieving rapid construction of high-speed railway bridge structures. To investigate the mechanical properties and reliability of the PHCBDCSS under earthquake excitations, full-scale pier in-situ pseudo-static test and numerical simulation of a practical high speed railway PHCBDCSS are performed. Accordingly, the damage state and damage characteristics of PHCBDCSS are analyzed, and the seismic performance is assessed in terms of strain distribution, hysteresis curve, stiffness degradation and ductility, as well as the sensitivity of spigot and socket connection piers to the stiffness of spliced joints is revealed. The results show that the socket connection of PHCBDCSS can effectively and reliably transfer the applied load, which meets the design requirements. Similar to the cast-in-place integral pier, the failure mode of PHCBDCSS is a typical plastic hinge bending failure. Moreover, PHCBDCSS and cast-in-place integral pier have good plastic deformation capacity, bearing capacity and member ductility. The key points of the pier hysteresis curve obtained from fiber element simulation are in accordance with the test results. When the ratio of connection joints' stiffness to pier columns' stiffness exceeds 10, the mechanical properties of the socket connection pier and the cast-in-place integral pier are similar.