Review of Devices for Preventing Bridge Structures From Unseating and Pounding Damages

Due to the insufficient width of expansion joints or excessive displacements of the girder, bridges could suffer serious seismic damages, such as unseating and pounding under severe earthquakes. This paper presented a comprehensive overview of various types of unseating and pounding prevention devices, such as restrainers, dampers and modular expansion joints, which reduce the earthquake damages, and a comprehensive discussion was carried out, in terms of merits and defects, design methods, and engineering practice of the unseating and pounding prevention devices. The design methods of unseating prevention devices at home and abroad were introduced and compared. A comparative analysis of the minimum support width in the seismic design codes of different countries and regions was carried out. Some pieces of advice and further development of unseating and pounding prevention devices in the strong earthquake area of China were also given in this paper.