Study on the dynamic contact relationship between layers under temperature gradients in CRTSⅢ ballastless track  

作　　者：Lei Zhao Guotang Zhao Guotao Yang Hao Jin Chenxi Li 

机构地区：[1]Railway Engineering Research Institute,China Academy of Railway Sciences Co.,Ltd,Beijing 100081,China [2]China State Railway Group Co.,Ltd.,Beijing 100844,China [3]School of Transportation,Southeast University,Nanjing 211189,China [4]School of Traffic and Transportation,Beijing Jiaotong University,Beijing 100081,China

出　　处：《High-Speed Railway》2024年第3期133-142,共10页高速铁路（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant No.52278466);the Project of China Academy of Railway Sciences Co.,Ltd(Grant No.2023YJ194).The useful contribution and discussions from project partners are also acknowledged.

摘　　要：In areas with large temperature differences,the uneven distribution of temperatures in the CRTS III ballastless track slab due to daytime sunlight can cause warpage deformation,leading to periodic rail irregularities that increase the wheel-rail impact of high-speed vehicles and accelerate track structure damage.Therefore,it is necessary to study the dynamic contact relationship between the composite slab and the base plate during vehicle running.The results of the study show that:1)Under the influence of temperature gradients,the composite slab tends to deform elliptically.With a positive temperature gradient,the middle part of the track slab bulges upward,causing the slab to be supported by its four corners.Conversely,with a negative temperature gradient,the four corners of the track slab bulge upward,resulting in the slab being supported by its center.2)Temperature gradients can lead to separation between the composite slab and the base plate,reducing the contact area between layers.During vehicle running,the contact area between layers gradually increases,but the separation cannot be completely closed.3)The temperature gradient significantly affects the vertical displacement of the track.The vertical displacement in the middle of the slab increases with a positive temperature gradient.In contrast,the vertical displacement at the ends of the slab increases with a negative temperature gradient.4)The stress of self-compacting concrete at the side position significantly increases under a positive temperature gradient,with the vertical stress increasing by 2.7 times when the temperature gradient increases from 0 to 90℃·m^(-1).

关 键 词：High-speed railway Ballastless track Temperature gradient Periodic irregularities Interlayer contact 

分 类 号：U213.244[交通运输工程—道路与铁道工程]