400km·h^-1高速铁路无砟轨道基床结构及关键参数研究  

Structural Analysis and Key Parameter of Ballastless Track Subgrade for 400km·h^-1 High-Speed Railway

作　　者：罗强[1,2] 张瑞国[1,2] 谢宏伟 田地[1,2] LUO Qiang;ZHANG Ruiguo;XIE Hongwei;TIAN Di(School of Civil Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China;MOE Key Laboratory of High-Speed Railway Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031

出　　处：《中国铁道科学》2020年第2期34-44,共11页China Railway Science

基　　金：国家自然科学基金资助项目(51878560);国家973计划课题(2013CB036204)。

摘　　要：为掌握列车荷载作用下路基应力概率分布特征,进行基于我国高速铁路无砟轨道不平顺谱条件下的车辆-线路耦合动力学计算;以路基累积变形效应区不超过基床范围为原则,分析基床厚度与基床以下路基性质的相互关系;结合模型试验获得的填料累积变形状态阈值,基于强度、变形、应变控制准则,进行400km·h^-1行车条件下的无砟轨道基床结构及关键参数研究。结果表明:路基面承受的列车荷载随轨面平顺性呈明显的随机变化特征,动力影响系数服从正态分布,轨道极端不平顺引起的最大动力影响系数为2.146,平均轨道谱下的常遇动力影响系数为1.491;路基累积变形效应区范围随填料强度降低而扩大,基床厚度为2.7m时,由低塑性土填筑的基床以下路基K30应大于等于100MPa·m^-1;以调控累积变形处于快速收敛状态为目标,提出基床表层采用0.7~0.3m厚级配碎石进行强化处理,K30大于等于190 MPa·m^-1,底层选用A,B组填料,相应K30控制值为130~150MPa·m^-1。In order to know well the probability distribution characteristics of subgrade stress under train load,the calculation of vehicle-track coupling dynamics is carried out based on PSD of ballastless track irregularities of high-speed railway in China.Under the principle that the cumulative deformation effect area is not more than the subgrade,the matching relationship between the subgrade thickness and the filler properties is analyzed.Based on the strength,deformation and strain control criteria,the structure and key parameters of the ballastless track subgrade under 400 km·h^-1 are studied combined with the cumulative deformation state threshold obtained from model tests.Results show that the train load on the subgrade surface changes randomly with the track irregularity,the dynamic influence coefficient(DIC)follows the normal distribution,and the maximum DIC of the ultimate load caused by the extreme irregularity of the track is 2.146,while the DIC of normal load under the average track spectrum is 1.491.The effect area of subgrade cumulative deformation increases with the decrease of filling strength.When the thickness of subgrade is 2.7 m,the subgrade coefficient K30 of embankment below the subgrade filled with low plasticity soil should be greater than or equal to 100 MPa·m^-1.Regard the cumulative deformation is in the immediate stabilization as the control target,it is proposed that 0.7~0.3 mthick graded gravel should be used to strengthen the surface layer of the subgrade,and K30 should be greater than or equal to 190 MPa·m^-1.Group A and B fillers are selected for the bottom layer,and the corresponding K30 control value is130~150 MPa·m^-1.

关 键 词：高速铁路 基床 参数 累积变形 状态控制 概率分布特征 

分 类 号：U213.1[交通运输工程—道路与铁道工程]