Design And Optimization Of Prefabricated Fabricated Rail Structure For Mountain High Speed Railway Tunnel

The smoothness and stability of high-speed rail tunnel under rail structure is one of the prerequisites for ensuring the safe operation of railway lines.Due to a series of deficiencies in the design and construction of the rail structure under the traditional high-speed rail tunnel,under the combined action of external factors such as train vibration and ground water and surrounding rock pressure,many kinds of hidden dangers such as delamination,cracking,floor heave,subsidence,mud boiling and mud erosion have occurred.With the massive construction of high-speed railway tunnels in China,the safety of trains has put forward higher requirements for the quality of tunnel under rail structure.In order to ensure the safety of high-speed railway tunnel operation,it is of great practical significance to propose a new type of high-speed rail tunnel under rail structure.In this paper,data analysis,data statistics and numerical calculation are used to analyze the disease characteristics of high-speed railway tunnels,and the design schemes for precast and fabricated rail structures of different high-speed railway tunnels are presented.(1)This paper investigates the defects of rail structure in high-speed railway tunnels during operation period,and reveals the different diseases of rail structures under existing high-speed railway tunnels in China.By using data statistics and engineering analogy methods,it summarizes the disease types of existing high-speed railway tunnels under rail structure,and analyzes the causes and influencing factors of main diseases under the structure of high-speed railway tunnels.The main common diseases of high-speed rail tunnel under rail structure have been grasped.(2)The relevant theories and engineering applications of prefabricated assembly technology in tunnel engineering at home and abroad are investigated and analyzed.According to the relevant specifications and structural requirements of the high-speed rail tunnel,a variety of different types of precast and fabricated rail structure design schemes for high-speed railway tunnels are put forward,and the structural stability and stress conditions of the corresponding design schemes are analyzed,and different types of structures are obtained.The advantages and characteristics of the new high-speed rail tunnel precast structure design scheme.(3)Based on the Zheng Wan high speed railway tunnel project,a new precast and fabricated rail structure design for a typical high-speed railway tunnel with typical section is proposed.Based on the actual working conditions,the static and dynamic responses of the new precast and assembled rail type single track and double track trains at different speed conditions during the construction period and operation period are analyzed,and the stress and the structure under the rail are revealed.The evolution rule of strain has mastered the main factors affecting the stress of the rail under the high-speed rail tunnel.(4)Considering the longitudinal and circumferential connection of precast fabricated rail structure of high-speed tunnel,a new type of connection structure for precast and fabricated rail structure of railway tunnel is put forward.Considering the waterproof and drainage system of precast fabricated rail structure of high-speed tunnel,a new type of precast and fabricated rail drainage and drainage system for railway tunnel is put forward innovatively.(5)Considering the construction of precast fabricated rail structure of high-speed railway tunnel,the construction technology for different prefabricated invert structure,filling layer structure and connection structure design is put forward,which embodies the advantages of prefabricated structure and provides the foundation for construction design of prefabricated tunnel development.