| Economy under the new normal, along with our country put forward "area all the way" strategic objectives, and construction of rail transit in C hina not only the main way of transportation and the pillar of the national economic and social development. The railway transport have a lot of advantages, such as safety performance is good, time punctuality rate is high and fast, low energy consumption and environmental impact light ly, covers an area of less, and so on.So it obtained the rapid development in the countries all over the world. However, with the market construction development, train running time, carrying the weight and traffic density more and more increaser. the high speed of the train over- load makes between vehicle and track structure enhanced dynamic role increasingly,and affecting train safety, riding comfort and reliability o f track structure dynamics problems also increasingly significant. Therefore, it is necessary to study of vehicle-track system coupled dynamics problem analysis. The main work and research contents are as follows:(1) According to coupled dynamics theory in the structure of vehicle-track system, base on the vehicle system and track structure of reasonable simplification and assumption, a vehicle-track vertical coupled dynamics calculation model of structure system have established; Equivalent processing according to the theory of nonlinear spring contact between vertical wheel/rail contact forces.In accordance with the "accordingly" method, stiffness matrix and mass matrix of the vehicle system, and damping matrix track structure have established respectively. Finally, setting the total of the whole system matrix differential equation of movement of the vehicle and track structure vibration differential equation.(2) In plane based on the theory of static wheel/rail contact geometry relationship, with the aid of auxiliary software for discrete points after type is deduced and the type and level of rail wheel tread profile type of mathematical expression and the computer program was written on the basis of this, the wheel/rail is used to calculate plane static contact point and then by comparing the minimum vertical distance locate wheel/rail contact points.(3) The paper introduces the pulse type is not smooth, harmonic uneven and several common types of track irregularity and function expression. And also make a different track irregularity of time-domain samples as input turbulence.(4) In the paper introduces the two types of vertical coupled dynamics numerical analysis method, four kinds of implicit method including the methods, such as Park, Newmark,Houbolt and Wilson-β. Two methods of explicitly include center difference method and Zhai Wan- ming new display of integral method is put forward. Combining with the characteristics of various numerical methods applied in the dynamic model is put forward the solving steps, lists the program flow chart of system for numerical calculation program is compiled to applied to solving dynamic equation model.(5) The vertical coupling system dyna mics model which track irregularity as the input time domain samples have established. And using time domain numerical integral method of the system calculation and analysis the random vibration response of the law. On this basis, the different numerical integration method for track irregularity incentive structure of vehicle-track coupling system under the basic law of random vibration, the numerical analysis methods in the dynamic model of the application is of important theoretical significance.(6) By calculation with harmonic model is not smooth, short wave irregularities and 6 of the United States under the effect of turbulence spectrum and kinds of track irregularities to anylize the fixed models, Through the system structure of vehicle-track coupled vibration response under different numerical integral method, it have find that advantages and dis advantages to various numerical integration methods of calculation.(7) Compared implicit method and center difference method, a new explicit method of integration process is relatively simple. No matter how complex, the damping matrix in the process of integral equations of mass matrix is a diagonal matrix or after diagonalization, And it do not need to solve the linear algebraic equations. Equivalent calculation under the condition of not only save the computational memory and time, and on the analysis of the actual engineering of large nonlinear structural dynamic problems can significantly improve the computational efficiency and economy.(8) Through analyzes the wave type harmonic kinds of track irregularities which have changes deeply in the structure of vehicle-track vertical coupled vibration response of the system, it have find some regularities.(9) Analysis of different fastener and ballast stiffness value of vibration system, along with the increase of stiffness, the vertical acceleration maximums of the rail, sleeper and ballast bed is not a linear increase, but in a stiffness value reached the peak, when the stiffness value add vertical acceleration instead of down. |
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