Analysis Of Vibration Characteristics Of Steel Spring Floating Slab Track For 160km/h Metropolitan Rapid Rail

Metropolitan rapid rail can effectively connect the main urban area and the remote urban areas,and speed up the circulation of resources and personnel within the metropolitan area.Compared with urban rail transit,metropolitan rapid rail has higher train running speed and larger axle load,which is accompanied by more serious vibration and noise problems.It is particularly important to choose a suitable vibration damping track.The steel spring floating slab track is mainly used in urban rail transit with a speed of 100 kilometers per hour and below.There are few examples of it used in the metropolitan rapid rail,and the research on the adaptability of the steel spring floating slab under the working condition of the metropolitan rapid rail is insufficient.Therefore,it is of certain significance to carry out the research on the steel spring floating slab track structure of the metropolitan rapid rail.Based on the research background of the adaptability of the steel spring floating slab track on the metropolitan rapid rail,this paper mainly carries out the following researches on the vibration characteristics of the assembled steel spring floating slab:(1)Establish a finite element model of an assembled steel spring floating slab track to study the influence of track structural parameters on the natural frequency of the system.The natural frequency of the assembled steel spring floating plate is relatively low,the first three natural frequencies are: 9.80 Hz,10.98 Hz,14.60Hz;the low-order natural frequency of the steel spring floating slab track is related to the length,width,thickness and isolator spacing are negatively correlated,and positively correlated with isolator stiffness.The change of isolator stiffness and spacing has a more significant impact on the low-order frequency of the floating slab track.(2)The train-floating slab-tunnel coupling dynamic model is established,the influence of train speed and vibration isolator stiffness on the dynamic response of the system is analyzed,the vibration reduction performance of different working conditions is compared,and the arrangement of the limit device is proposed.Program.The prefabricated steel spring floating slab track meets the safety and stability requirements of urban trains when running fast;The transverse and vertical vibration acceleration of the train and the vertical displacement of the structure are negatively correlated with the stiffness of the isolator.When the stiffness of the isolator increases from 7.5k N/mm to 15.0k N/mm,the vertical displacement of the rail and the floating plate decreases by30.2% and 41.6%.After the rigidity of the vibration isolator continues to increase,the influence on the displacement is reduced.The stiffness is negatively correlated,and the vibration reduction effect of the floating slab track can reach more than 15 d B under different isolator stiffnesses,and the vibration reduction performance in the high frequency band is particularly outstanding.(3)Through static and dynamic calculations,the restraint effect of shear hinges and shared isolators on plate end displacements at plate joints is analyzed.Adding a shared vibration isolator is beneficial to reduce the vertical displacement of the long plate and the rail plate end,while adding a shear hinge and a shared vibration isolator has a better effect on the restraint of the plate end.