Study Of The Vertical Line Stiffness Design Of Bridge Pier Laying Cwr

The longitudinal stiffness of pier is the key parameter in designing bridge and continuous welded rail (CWR), the distribution of longitudinal force between rail and pier largely depend on the longitudinal stiffness of pier. In our country, the bridge accounts for the proportion to be getting higher and higher in new railway. The study of longitudinal stiffness of pier impact on the CWR, and thus put forward the design requirements and reasonable limits of the longitudinal stiffness of pier, that is of great realistic significance in designing CWR, pier and foundation of bridge.This paper firstly summarizes the general situation cf design and calculation of CWR on bridge, and then emphatically analyzes the definition and applications of longitudinal stiffness of pier at home and abroad. Secondly, this paper makes a comparative analysis of the control conditions and Influencing factors of CWR on bridge at home and abroad. The influencing rules of longitudinal stiffness of pier inpact on the force and displacement of CWR on bridge are emphatically analyzed. And the viewpoint, that is when the stiffness difference of adjacent pier is oversized, the additional force especially braking force acting on the pier having bigger longitudinal stiffness and the track/bridge relative displacement will greatly increase is put forward. The paper make a suggestion, in design of CWR on bridge, not only the limits of longitudinal stiffness of pier should be taken into account, but also the stiffness difference of adjacent pier should be designed equably, and larger difference of the adjacent pier stiffness should be prevented. When unusual stiffness difference of adjacent pier appears, we should make a calculation and check particularly, instead of conforming to norms.Finally, the paper carried out a detailed calculation and analysis about the longitudinal stiffness of pier impact on the CWR of common bridge (simple beam, continuous beam, continuous rigid frame). From the safety and saving investment point of view, the paper put forwaed a more reasonable limit of the longitudinal stiffness of pier, that can be used as reference in designing.The conclusion of this paper is of great guiding significance in designing of CWR on bridge, pier and foundation of bridg. The study concludes provide a reference in compilation of Railway design code about continuous welded rails.