Numerical studies on the seismic responses of precast segmental columns-supported bridge structures subjected to near-fault ground motions

Precast segmental columns have attracted wide attentions in bridge construction industry recently due to its ability to accelerate construction speed, improve construction quality and reduce environmental impact. It is of great practical importance to study the seismic performances of segmental columns, and many experimental and numerical studies have been performed. However, most previous studies focused on segmental column itself, the research on the seismic performance of a whole bridge structure supported by precast segmental columns is very limited. In particular, no systematic studies have been performed to investigate the seismic performances of segmental columns-supported bridges subjected to near-fault (N-F) ground motions (GMs). To bridge this research gap, the seismic responses of three bridge structures (i.e. a segmental columns-supported bridge, a bridge supported by segmental columns with internal energy dissipation bars, and a conventional bridge supported by monolithic columns) subjected to four types of earthquake ground motions (i.e. a N-F GM with fling-step (F-S) effect, a N-F GM with forward-directivity (F-D) effect, a non-pulse-like N-F GM, and a typical far-field (F-F) GM are investigated and compared in the present study based on the validated numerical models developed in ABAQUS. The influences of permanent ground displacement in the F-S ground motion and pulse period are also systematically investigated. The numerical results demonstrate that the permanent ground displacement in the N-F ground motions has very different effects on the segmental-columns supported bridge and monolithic columns supported bridge.