Study On The Application Of A Simulation Method Of Coupled Vibration Of Modern Tramcar And Track Structures

Developing public transport mode that has a certain volume,low energy consumption,small investment,short cycle and environmental protection is an important means to solve the traffic congestion problem of small and medium cities in China,which is also an important reason for the construction of modern tramcar system in china.However,with the rapid development of tramcar in China,it also brings a lot of more prominent problems,such as the problems of vehicle rail coupling vibration,whether the dynamic performance of tramcar meets the operation requirements,etc.Under this background,firstly,the method of wheel rail coupling using multi-body dynamics software SIMPACK is introduced,and for the problem that the vibration response of the coupled system can not be comprehensively analyzed by Previous coupling methods,an improved method of wheel / rail coupling based on multi-body dynamics and finite element method is proposed by using the *.ftr file of the rail and the flexible track module of SIMPACK;and then established the four module "ADtranz" type of modern tramcar,analyze the dynamic performance of vehicle;finally,the coupled vibration analysis model of the modern tramcar-ballastless track-ground is established by the wheel rail coupling method in this paper,and the propagation law of the ground vibration induced by tramcar is studied,the result shows:(1)The wheel rail coupling method in this paper is not only applicable to the coupling between vehicles and the ground,but also to the coupling between vehicles and bridges;(2)The nonlinear critical speed of the modern tramcar is 143km/h,which can meet the requirement of the highest design speed 70km/h of the modern tramcar;(3)The vehicle speed increase will make the vehicle acceleration vibration response increased significantly,especially the transverse vibration acceleration response;with the increase of vehicle speed,both the vertical and horizontal riding index increase;when the vehicle speed is not less than 30km/h,the same speed,vehicle lateral stability index is greater than the vertical stability index,and when the speed reaches 90km/h,the vehicle lateral stability index reached 2.843,the lowest level stability has been very close to the GB5599-85 limit,therefore,the lateral vibration of car body should be paid more attention to in the design of vehicle vibration control;(4)The derailment coefficient and the wheel load reduction rate of the wheel-set of the modern tramcar are less than the second limit specified by GB5599-85,which shows that the tramcar has good curve passing performance;(5)The earth surface vibration attenuation rapidly in the track from the center line about10 m distance,more than 10 m after decay slowly;the vertical vibration of transmission about rapid decay in the depth range of 6m,more than 6m decay rate is slow;whether the vibration is propagating along the surface or vertical propagation,the vertical vibration of the observation points is greater than the transverse vibration,so the vertical vibration should be paid more attention to when studying the earth vibration induced by the tramcar;(6)The nearer the distance from the source of vibration,the more peak frequency,the main frequency of the closest observation point from the vibration source is 30.6Hz,this is from the track irregularity excitation caused;As the distance increases,the peak frequency is reduced,the main frequency changed to 6.3Hz,and the peak frequency of each measuring point is similar,This is related to the dispersion characteristics of the earth vibration.When the vibration propagates in the earth,the low frequency vibration attenuates slowly,and the high-frequency vibration decays rapidly;(7)The attenuation of the surface vibration of the earth is very slow at 4Hz and 6.3Hz,and the phenomenon of vibration amplification occurs at 6.3Hz,which is due to the fact that the excitation frequency is similar to that of the earth frequency(6.3Hz).