Mechanical Properties and Structural Optimization of Continuous Welded Rail on Super-Long-Span Suspension Bridges for High-Speed Railway

Tielin Wang,Tao Wang,Guanyuan Zhao,Wanli Liu,Xiaopei Cai

doi:10.3390/app12010305

Abstract

In order to ensure driving safety and comfort, it is necessary to figure out the complex interaction between continuous welded rail (CWR) and suspension bridges for high-speed railway. A spatial finite element model for a 1092 m main span suspension bridge was established based on the bridge-track interaction theory. A specific correction method was put forward to keep the rail in a zero-stress state when just laid. Three rail expansion joint (REJ) layout schemes were proposed according to practical engineering experience. Both static and dynamic analysis methods were used to evaluate the feasibility of these schemes. The results show that the REJ should be laid at the position with a distance away from the primary beam end, and the beam with more substantial integral stiffness should be preferentially selected. For the recommended scheme, the REJ expansion reaches more than 380 mm under expansion load. The factors affecting the REJ expansion from major to minor are temperature, earthquake, rail fracture, braking, and bending load. The superposition effect of the above factors is suggested to be considered in the selection of REJ range.

Highlights

With the large-scale construction of the railway in China, super-long-span suspension bridges have gradually been popularized and applied in high-speed railway construction [1], considering the engineering economic factors when crossing complex river systems and geology
The suspension bridge is known for strong crossing capacity, convenient construction, and beautiful appearance, the bridge and the continuous welded rail (CWR) laid on it form a complex spatial coupling model
The track and large-span bridge have been investigated in different aspects, including: analytical algorithm of the bilinear resistance model [2]; nonlinear finite element model (FEM) [3,4,5,6,7]; nonlinear static analysis program using a truss model [8]; static and dynamic analysis of cable structures based on catenary cable element [9]; design optimization for primary beam shape and plate thicknesses of long-span suspension bridges [10]; and the distribution of rail longitudinal force on large-span bridges [11,12,13,14]

Summary

Introduction

With the large-scale construction of the railway in China, super-long-span suspension bridges have gradually been popularized and applied in high-speed railway construction [1], considering the engineering economic factors when crossing complex river systems and geology. The track and large-span bridge have been investigated in different aspects, including: analytical algorithm of the bilinear resistance model [2]; nonlinear finite element model (FEM) [3,4,5,6,7]; nonlinear static analysis program using a truss model [8]; static and dynamic analysis of cable structures based on catenary cable element [9]; design optimization for primary beam shape and plate thicknesses of long-span suspension bridges [10]; and the distribution of rail longitudinal force on large-span bridges [11,12,13,14]. Most existing studies only focus on cable-stayed bridges, to the neglect of the suspension bridge The latter will drive CWR to produce larger deformation under the load of the train, because of its flexible system, posing a huge challenge to the stability and comfort of high-speed railway. It is necessary to figure out the interaction mechanism of CWR on suspension bridges

Methods

Results

Conclusion