ABSTRACT
This paper aims to study the limit span of continuous railway bridges without the setting of the rail expansion devices for continuous welded rail (CWR) on the bridges. The track-bridge interaction models are established for both three-span continuous bridges and continuous rigid frame bridges with different main spans. The additional stress of CWR on bridges and the relative displacement between the bridge and the rail are calculated under the effects of both train braking and temperature variation. The results show that the rail additional stress increases linearly with the increase of the temperature span. It is necessary to set up the rail expansion devices on three-span continuous bridges when the temperature span exceeds 220 m. The continuous rigid frame bridge can notably reduce the rail additional stress and thus a larger limit temperature span can be gained.
