Study On Setting Method Of Rail Transit Segment Of Steel Spring Floating Slab In Urban Rail Transit

In the modern society, the scale of the city continues to expand, the problem of traffic congestion is becoming more and more serious. Subway and light rail traffic with its large capacity, running on time, take convenience and comfort and other advantages have been the main way to ease the pressure of modern urban traffic, to solve traffic congestion in large cities. In this paper, The steel spring floating slab track structure which a kind of urban rail transit for special damping areaes as the study object, the main purpose is through analysising and researching the dynamic characteristics of transition section between the floating slab track and common monolithic track bed in different transition way to make recommendations for practice.As a basis of reseaching the dynamic characteristics of the metro vehicle-track transition section between the general overall track and the floating slab track. firstly, we need have a thorough understanding of dynamic characteristics of Vehicle-Track Coupling System vertical vibration, for this reason, this article first introduces in detail the vehicle-track coupling system of finite element modeling method and modal modeling method and use the two methods respectively, write the MATLAB simulation, based on the program, the third chapter compares the two kinds of dynamic modeling method above and verify the validity of the program, the main conclusions:For the acceleration and the displacement of the vehicle body, the two methods have obvious consistency. On the contrary, when the rail displacement and rail acceleration are discussed, there is a big difference.Compared with the finite element method, the dynamic response of the modal method is more extensive, but the accuracy is lower. The most important point is that the modal method greatly reduces the degree of freedom of the Vehicle-Track coupling vibration equation and improves the operation speed.The mode method and the finite element method are quite similar to the difficulty of solving process.Based on the above conclusions, this paper establishes a subway train-floating slab track transition section finite element model. which uses the vehicle model B subway car, floating slab track transition model includes ordinary monolithic track bed model, transition model and steel spring floating slab track model,at the same time, selection the type A(6.6MN/m) steel spring under the floating slab. On the basis of reading a great amount of literature, a variety of transition programs are proposed, and the excellent transition means are found by MATLAB simulation. The final results are as follows:(1) By using the elastic supporting block track transition section can effectively solve the dynamics problems caused by foundation stiffness irregularity. which long sleeper elastic supporting block is a little better than the short sleeper elastic supporting block.(2) When the sleeper spacing is 0.6 meter, the dynamic response of each part are in good condition. The design value is consistent with the actual value.(3) Suggested that the stiffness value of steel spring under the floating slab where is in the transition section range 2 3K_s from 8K_s. in order to play a good transition effect.(4) The fifth kinds of combinations of "grading transition " are the best methods, the transition methods which transversely encrypting steel spring and "function transition" can get better results.