| Turnout is one of three principle weak links of railway tracks, and it is the key factor of limiting high-speed EMUs and heavy load trains. The most important characteristic of the turnout is the cross-sections of tracks are varying along track-length, it makes some transverse irregularity and vertical irregularity existing in the turnout. This paper established two turnout models by the multi-bodies dynamic software, named SIMPACK. This two turnout models are established by the accurate geometrical size and cross-section drawings of18#and42#high-speed turnouts.The variable cross-section characteristic of the turnout determines the complex wheel/rail contact relationship. In the region of railroad switch and frog, the loads are supported by blade and stock rail or by wing rails and nose rails, so, multiple contacts and transverse impact between the wheel and the rail must be happened. Because of guard rail, violent impacts are happened between the back of the wheel and guard rail. When the trains are running at a high speed, because of natural irregularity of the turnout structure, the wheel may lose its contact in a moment. Dynamic responses of high-speed EMUs are obtained by SIMPACK while driving though the turnout in this paper, and the contact problems and the dynamic problems must to be taken into account.One kind of accurate mathematical simulation model of high-speed EMUs with one motor car is established by SIMPACK. So, vehicle-turnout coupling dynamic model with the variable cross-section turnout model which is established by real size and layout is built up. Simulation calculation for the effects of key suspension parameters of the bogie to the dynamic responses of the high-speed EMUs while though42#high-speed turnout, then, optimizing suspension parameters of the bogie of the high-speed EMUs. In this way, hope to improve the condition of more serious vibration even instability while the high-speed EMUs though the turnout, thereby, vehicles can drive though the turnout with best dynamic responses.At last, the dynamic responses of the high-speed EMUs while though18#and42#high-speed turnouts on the divergent route and the major track are obtained by simulation calculation, and compare the results. |
