Abstract

Under strong earthquakes, bearings of cable-stayed bridges usually separate from the main beam.

This paper adopts a cable-stayed bridge as the background project to study the influences of

bearings unseating. Moreover, the effects of auxiliary piers on bearings unseating of cable-stayed

bridges subject to earthquakes are also researched. Numerical results show that bearings unseating

that may happen on transition pier and main tower result in large vertical displacement of main

beam and bearings pressure. The position of auxiliary pier on the side span has an important

influence on the bearings compressive force and girder vertical displacement of transition pier.

Increase of bearings constant load pressure of auxiliary piers can reduce the vertical displacement

of girder to some extent. However, the large bearings constant load pressure may causes large

pounding force that should not be neglected in cable-stayed bridges design.

Keywords: cable-stayed bridge; unseating; seismic design; auxiliary pier; constant load pressure