Study On Analysis Theory Of Running Safety Of High-speed Train On Ballastless Track Of Passenger Dedicated Lines And Its Application

Ballastless track is the development trend for track structure of high-speed railway. In China, passenger dedicated lines with the main track structure type of ballastless track laid by section, are being constructed on great efforts. Although a lot of theoretical and experimental studies have been done, the construction of ballastless track of passenger dedicated lines lakes of mature experience and depends on import of foreign technologies. So, how to understand, digest, assimilate and re-innovate foreign ballastless track technologies, as well as how to make foreign things serve China finally, is the task of top priority. It is more important to guarantee the higher degree of safety of high-speed train running on passenger dedicated lines and direct the design, construction and operation of ballastless track according to the conclusions of theoretical analysis. To solve the above problems through theoretical research will be of great theoretical value and social and economic benefit. The main research results of the dissertation are as follows.1. The analysis theory for the spatial vibration of high-speed train and ballastless track time-dependent system is put forward and the main contents of the theory are as follows.(1) Based on the lateral finite stripe and slab segment element, the analysis model for spatial vibration of ballastless track is estabilished, and the total potential eneygy of spatial vibration of the track is deduced.(2) The high-speed train and the ballastless track are taken as a whole system. Based on the principle of total potential energy with stationary value in elastic system dynamics and the rule of "Set-in-right-position" for formulating system matrixes, the spatial vibration equation set of the high-speed train and ballastless track time-dependent system is established considering the wheel levitation, the connecting condition of displacement between wheel and rail and the influence of the clearance between wheel flange and gauge line.(3) The crawling wave of high-speed bogie and the vertical irregularity of track are regarded as the exciting sources of lateral and vertical vibration, respecitively; and the equation is solved by the numerical integration method of Wilson-θ.(4) Based on the Fortran PowerStation 4.0 developping plateform, the corresponding computer program is programmed by the computer language of Fortran.2. The spatial vibration responses of the system are calculated. The comparison between the calculated and measured results is made. And both the caculated response waveforms and values of the system are in accord with the physic concepts. All of these demonstrate the correctness and feasibility of the analysis model and the program.3. The recommended ranges of the design parameters of ballastless track structure are put forward according to the analysis of effect of parameters of train and track on the spatial vibration responses of the high-speed train and ballastless track time-dependent system. Above all, the new viewpoint that the cement asphalt mortar, i.e. CAM, should have higher strength and lower elastic modulus is proposed. And it directs the technical direction for the research and development of CAM. Based on the parameter in this paper, the CAM material researched by Central South University has been applied to the ballastless track test section with the length of 5 km on the Wuhan-Guangzhou passenger dedicated line.4. Based on the theory for energy random analysis of train derailment, the whole derailment course of the high-speed train running on the ballastless track is simulated. And the vibration responses of the whole course of high-speed train derailment have been calculated for the first time, and the relationship between the workσc done by the limited resisting force of the lateral vibration of the system and the train speedⅤis obtained. Aimed at the typical ballastless track structures of Chinese passenger dedicated lines, the running safety of high-speed train running on the ballastless track within the design speed is analyzed and the degree of safety is calculated.5. Based on the theory for energy random analysis of train derailment, the concept and calculation method of critical vehicle speed of lateral vibration instability of train-track time-dependent system is put forward, and the critical speed and the permissible limit speed with the safety coefficient K have been calculated for the first time. 6. The analysis method for spatial vibration of cross wind-train-track time-dependent system is established. The effect of cross wind on the spatial vibration responses of high-speed train and ballastless track time-dependent system is studied, the influence of cross wind on the running safety of high-speed train running on the ballastless track is analyzed, the whole derailment course of the high-speed train in cross-wind is simulated, and the critical wind speed controlling derailment is obtained.