Study On Structure Parameters Of Low Vibrationtrack In Heavy Haul Railway Tunnel

In recent years,the development of heavy haul transportation has made great progress.In order to adopt to the requirement of the modern logistics,the heavy load transportation technology with heavy axle load and high efficiency must be vigorously developed.Adopting ballastless track structure in heavy haul railway tunnel has a series of advantages,including lowing tunnel clearance,strength structure durability,reducing maintenance workload as well as keeping a stable geometric shape and so on.Low vibration track(LVT) is one kind of ballastless track structure that can absorb shock and reduce noises,and is suitable for laying in heavy haul railway tunnel. Therefore,on the basis of sufficient analysis of LVT structure forms and its distinctive features,studying on structure parameters of LVT under payload conditions can provide a reference for the future designing of LVT structure in railway tunnel and that research can also promote LVT structure forms be further popularized and applied.Structural parameter optimization of LVT in heavy haul railway tunnel were carried out by analysing the influencing laws of the indexes,including keeping the geometry,dynamic response and stress state of the track structure and all of the indexes can be affected by the geometry of supporting block and the stiffness under the supporting block.The main researches are listed as follows.(1)A finite element model of the LVT in heavy haul railway tunnel was built by using finite element analysis software-ANSYS.(2)Some calculations are conducted by using this model,including the changes of horizontal and vertica displacement of rail and supporting block,rotating angles under the different size of supporting block and the reasonable gradient of short side,length, and embedded depth value ranges of supporting block is given under the condition that the axle load on rail is 30 t of LVT in heavy haul railway tunnel.(3)Based on landing wheel axle simulation experiment,the stiffness under the supporting block was studied to explore the respective stiffness selection issue of the rubber padding under the supporting block and elastic shoe and to determine the reasonable value range of rail stiffness between them.(4)In combination with the actual example of HeShun to XingTai railway(HeXing railway),the structure parameter of LVT in HeXing railway tunnel was designed on the basis of the above research results.Finally,this thesis can provid a reference for the design and application of the LVT in heavy haul railway tunnel in the future.