Track-bridge Longitudinal Force Of Continuous Bridge On High-speed Railway With The Shrinkage And Creep And Sunshine Temperature Difference

The control of additional longitudinal forces at continuous welded rail (CWR) on high-speed railway bridge is one of the key technologies to ensure the smooth operation of high-speed train. However, only the calculation methods of telescopic additional forces, deflection additional forces and additional brake forces at continuous welded rail on high-speed railway bridge are prescribed by railway CWR design specifications. While the calculation methods of additional creep forces and sunshine temperature additional forces is given. Thus, aiming at high-speed rail standard span continuous beam bridge, the additional longitudinal forces at continuous welded rail on high-speed railway bridge are discussed and researched in this paper.1、By using the ideal elastic-plastic longitudinal resistance model, a pier-beam-track integration finite element model which could calculate the track’s additional longitudinal forces is established. Next, by taking the standard56m-span continuous beam bridge with ballastless and multiple tracks on high-speed railway as project example, according to railway CWR design specifications, the values and distribution patterns of telescopic additional forces, deflection additional forces and additional brake forces of high-speed railway continuous beam bridge are discussed. In this foundation, the s tracks’structure intensity is analyzed and calculated. While taking the rigidity of brake pillar on continuous beam bridge as the influence factor, the influence of the rigidity of brake pillar to additional brake forces is discussed.2、Based on the creep mode prescribed by China railway specifications, CEB-FIP1990specifications and ACI209(82) specifications the additional contraction creep forces at continuous welded rail on high-speed railway continuous beam bridge are analyzed. The influence of contraction creep to tracks’ additional longitudinal forces is quantified. The continuous beam bridge construction phase is fully simulated. And the influence of different keep-beam time to tracks’final additional longitudinal forces is discussed. 3、By using sunshine temperature mode of China railway specifications, the sunshine temperature additional forces at continuous welded rail on high-speed railway continuous beam bridge is calculated and the influence of sunshine temperature to tracks’ additional longitudinal forces is quantified. Finally, aiming at the green bean slope extra large bridge in Kunming Shanghai high-speed railway in Liuyang Changsha, the actual beam cross-section temperatures are measured. Based on the measured temperatures, the actual sunshine temperature curve is fitted and its coMParison with tracks’ additional longitudinal forces prescribed by specification is given.