Study On Frame Girder Ballastlss Track Of Elevated Station Arrival And Departure Track

On most station lines of passenger dedicated railway in China, ballasted track are applied. Many problems are caused on transit with ballastless track of main line rail, such as deviated stiffness transition, more maintenance and repairs, and therefore affecting operations; However, if ballasted track applied in main line are used in station line, difficulties in construction and too much cost would occur. Thus a structure that is relatively simple, economical and reliable should be designed.Ballastless track in station line is not only a combination of technical features and difficulties of ballastless track, but also involving a lot of technical issues such as station vibration and noise reduction, maintenance and repair, which are urgent to be solved in the construction of high-speed railway.In this paper, the design of frame girder ballastless track of elevated station arrival and departure track in high-speed railway is comprehensively researched, including mechanical models, computational methods, measurement and calculation method, etc. Theoretical basis of frame-type ballastless track design is provided. The main results of this dissertation are as follows:(1)Based on systematic summarization and analysis of the state of technical features, design methods and track dynamics research of ballastless track domestic and abroad, with considering the issues in the design of ballastless track of elevated station arrival and departure track in high-speed railway, a study of frame girder ballastless track is proposed based on the finite element method, aimed at reducing the track forces, deformation and vehicle dynamic performance.(2)In full consideration of structure characteristics and force mechanism of frame girder ballastless track system, a static analysis model and a vehicle-track coupling dynamic model of ballastless track frame were built. Vehicle, rail, fastener, and ballastless track components are modelled and the design of ballastless track in static and dynamic are implemented. The analysis model has also been verified.(3)The influence of train load, temperature load, and deflection of bridge to force and deformation of the bridge is analyzed. The results showed that the train load affected most, larger than the influence of vertical temperature load, deflection load, and longitudinal temperature load. Thus advices to designing are made.(4)The length of frame girder of high speed railway are analyzed deeply, based on the established theoretical models and load combination mode. Through analysis, the distribution of the vertical bending moment of the5450and6450type of slab bottom and roof are reasonable. It is proposed to comprehensively consider the static and dynamic characteristics, the technical and economic characteristics of the structure so as to design a reasonable frame ballastless track slab.(5)Through comparative analysis of three different programs of frame girder ballastless track, namely resisting shear stresses pin+rubber pad program, L-bearing+rubber pad program and resisting shear stresses pin+CA mortar program, it is showed by the static analysis results that resisting shear pin+rubber pad program is the optimal solution, followed by L-bearing+rubber pad, resisting shear pin+CA mortar the worst, while dynamic analysis results show that the three kinds of structural have little difference.(6)The stiffness of the rubber pad, mortar layer elastic modulus, and stiffness of fastening system of frame girder ballastless track have been analyzed, according to the analyzing results of their influence on ballastless track force and vehicle operation, and the stress analysis and comparison under different parameters, some suggestions about the proper value of reasonable parameters has been put forward.(7) Based on deep analysis of mechanical principle and checkup method of the pin of frame girder ballastless track of elevated station arrival and departure track in high-speed railway, Longitudinal stress and transverse force of pins were checked, combined with the analysis of impact of pin position on the track force, the pin arrangement mode is optimized, and principles of pin set is proposed in frame girder ballastless track for reference.The established design of frame girder ballastless track of elevated station arrival and departure track in high-speed railway is complete, with its calculation model and method correct, and the simulation results credible. Therefore it has significant importance to the design of ballastless station track of high-speed railway in China.