Study On The Design Of Urban Road Under-Crossing The Operational High-Speed Railway Bridge

China’s high-speed rail mileage has reached over 19 thousand kilometers by the end of 2015, and it has become the main travel mode of China’s railway passenger. In most parts of the country, more than 80% of high-speed railway lines are on bridges. When the urban road is about to be built or rebuilt, it often meets the situation of under-crossing the existing high-speed railway bridge, and the current high-speed railway bridge foundation deformation control standards are far higher than the normal-speed railway’s. In projects like this, how to solve the problem of control the influence to the foundation of the high-speed railway bridge during the construction and operation of the new project which under-crossing the high-speed railway bridge is a new problem. Based on this background, this paper launches the research.This paper base on a project of urban road going through under the Hangzhou-Ningbo high-speed railway bridge.It examines the current optimal scheme of simply supported girder bridge with pile capping beam. The influence of the construction of the new bridge under-crossing the high-speed railway bridge foundation is analyzed, and the results are compared with the monitor results, which proves the feasibility of this scheme and the reliability of the simulation analysis method.On the basis of this, the influence of the parameters such as the diameter of the pile, the spacing between the piles,the slurry and the load on the machine, which control the bridge deformation is discussed and some useful conclusions are drawn. At the same time, the conclusion of this paper can provide some references for similar projects.