Additional Temperature Forces of Continuous Welded Rail on Large-Span Steel Truss Cable-Stayed Bridge

Large-span steel truss cable-stayed bridge (Yuan-pei LIN,2004) appears in railway bridge construction in China, and the additional temperature force will inevitably become a controlling factor of paving continuous welded rail (CWR) on bridge (Ying HAO, 2002), but it has not been deeply researched based on calculation theory of CWR on bridges. So it is important to calculate the additional temperature forces of CWR of this bridge-type. Taking truss steel cable-stayed bridge of "5x32m simple beam + (36+96+228+96+36) m steel truss beam+5x32m simple beam" as an example, a bridge-rail interaction plane model was established, which could embody all structural characteristics of this bridge-type, such as steel truss, stay cable, main tower. And by using the finite element method (Xu-cheng WANG, 2003), the transmission mechanism of the additional temperature force was deeply studied, especially including influences of temperature change of stay cables and main towers. Finally the simplified algorithm of CWR design on this kind of bridge was proposed. Results show that distribution regularity of the additional temperature force of CWR on cable-stayed bridges is the same as that on common bridges, and paving CWR on this type of bridge is feasible; The increasing of cable stay's temperature can increase the additional temperature forces on rails, but the increasing of main tower's can decrease it, which shows that influences of temperature changing of stay cables and main towers should be taken into account when CWR on cable-stayed bridge is designed.