大温差地区CRTSⅠ型板式无砟轨道层间动态受力特征  

Characteristics of Dynamic Interlayer Stress of CRTSⅠBallastless Track in Regions with Large Temperature Differences

作　　者：赵磊 李浩 杨国涛 李晨曦 施成 宁娜 ZHAO Lei;LI Hao;YANG Guotao;LI Chenxi;SHI Cheng;NING Na(Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;National Key Laboratory of High-Speed Railway Track System,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;Huizhou Housing and Construction Apartment Section,China Railway Guangzhou Co.,Ltd.,Huizhou Guangdong 516023,China;Technology and Information Department,China State Railway Group Co.,Ltd.,Beijing 100844,China;School of Traffic and Transportation,Beijing Jiaotong University,Beijing 100081)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [2]中国铁道科学研究院集团有限公司高速铁路轨道系统全国重点实验室,北京100081 [3]广东铁路有限公司惠州房建公寓段,广东惠州516023 [4]中国国家铁路集团有限公司科技和信息化部,北京100844 [5]北京交通大学交通运输学院,北京100081

出　　处：《中国铁道科学》2024年第4期30-39,共10页China Railway Science

基　　金：国家自然科学基金资助项目(52278466);中国铁道科学研究院集团有限公司院基金课题(2023YJ194)。

摘　　要：大温差地区单元式轨道板受日照影响会产生较大温度梯度,导致轨道板翘曲变形,诱发轨面不平顺,增加高速列车轮轨冲击响应,加速轨道结构损伤。针对这一问题,采用有限元方法,首先建立考虑层间关系的无砟轨道静力分析模型,对大温度梯度下轨道板翘曲变形及轨面周期性不平顺进行分析;然后,建立车辆-轨道系统动力学模型,模拟分析温度梯度作用下无砟轨道层间动态受力特征,研究高速行车条件下无砟轨道真实服役状态。结果表明:温度梯度作用下,轨道板呈椭球形变形趋势,正温度梯度时轨道板中部向上鼓起、4角支承,负温度梯度时轨道板4角翘起、板中支承;温度梯度会导致轨道板与CA砂浆间产生不同程度离缝,板下接触面积减小,高速行车时层间接触面积逐渐增加,但离缝不会完全闭合;负温度梯度对轨道结构振动和砂浆层受力影响较小,正温度梯度影响较大,温度梯度为90℃·m^(-1)时,轨道板振动加速度增大10倍左右,轨道板与CA砂浆层间压力最大值增加6.6倍,板角处CA砂浆应力较无温度梯度下钢轨正下方CA砂浆应力增加5.4倍,正温度梯度下轨道板侧边及4角位置处CA砂浆受力加剧效应显著,是导致该区域CA砂浆出现结构性破坏的主要原因。In regions with large temperature differences,unit ballastless tracks are subjected to significant temperature gradients caused by solar radiation.This leads to the warping deformation of the track slabs and induces periodic irregularities on the track surface.This,in turn,increases the wheel-rail impact response of high-speed trains and accelerates damage to the track structure.To address this issue,a finite element method was adopted.First,a static analysis model of ballastless track considering interlayer relationships was established to analyze the warping deformation of the track slab and the periodic irregularities of the track surface under large temperature differences.Then,a vehicle-track system dynamics model was developed to simulate and analyze the dynamic interlayer stress characteristics of ballastless tracks under temperature differences and to study the actual service state of tracks under high-speed train operation.The results show that under the influence of temperature gradients,the track slab exhibits an elliptical deformation trend.Under a positive temperature gradient,the middle of the track slab bulges upwards with the four corners being supported,whereas under a negative temperature gradient,the four corners of the track slab lift up with the middle being supported.Temperature gradients result in varying degrees of gaps forming between the track slab and the CA mortar,reducing the contact area beneath the slab.Although the interlayer contact area gradually enlarges during high-speed train operation,the gaps do not fully close.Negative temperature gradients exerts a smaller impact on track structure vibration and mortar layer stress,while positive temperature gradients have a larger impact.When the temperature gradient reaches 90℃·m^(-1),the vibration acceleration of the track slab increases by approximately tenfold,the maximum pressure between the track slab and the CA mortar layer increases by 6.6 times,and the stress in the CA mortar at the slab corners increases by 5.4 times compared

关 键 词：高速铁路 CRTSⅠ型板式无砟轨道 温度梯度 周期性不平顺 层间接触 有限元 

分 类 号：U213.2[交通运输工程—道路与铁道工程]