行车速度对软岩填方路基动力响应的影响分析  

Analysis of Influence of Train Running Speed on Dynamic Response of Soft Rock Embankment

作　　者：焦梦雪 王俊杰[2] 吕川 王石焮予 JIAO Mengxue;WANG Junjie;LV Chuan;WANG Shixinyu(College of River and Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,China;College of Materials Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学河海学院,重庆400074 [2]重庆交通大学材料学院,重庆400074

出　　处：《交通工程》2024年第4期91-95,101,共6页Journal of Transportation Engineering

基　　金：重庆交通大学研究生科研创新基金(2022S0028)。

摘　　要：软岩地区修建铁路可采用开挖软岩作为路基填筑料,列车载荷作用下软岩填方路基的动力响应特征与路基变形及稳定密切相关,目前对列车载荷作用下软岩填方路基的动力响应研究仍不足。为了研究行车速度对软岩填方路基动力响应的影响,采用数值模拟方法,以动位移及竖向加速度为评价指标,分析了软岩填方路基的动力响应规律。结果表明:软岩填方路基在(200~400)km/h车速列车载荷作用下的最大沉降均超过现行规范允许的3 mm;路基动位移随行车速度的增大而增大,随深度增大呈减小变化;路基竖向加速度变化幅值随行车速度的增大呈增大变化,随水平距离增大而减小;行车速度越大,竖向加速度的衰减速率越小;软岩填方路基经CFG桩处理后,路基的最大沉降、动位移、竖向加速度均有所减小,表明CFG桩处理后软岩填方路基的动力特性有所改善。Soft rock excavation can be used as subgrade fill material for railway construction in soft rock area.The dynamic response characteristics of soft rock fill subgrade under train load are closely related to the deformation and stability of subgrade.In order to study the influence of driving speed on the dynamic response of soft rock fill subgrade,the dynamic response of soft rock fill subgrade was analyzed by numerical simulation method with dynamic displacement and vertical acceleration as evaluation indexes.The results show that the maximum settlement of soft rock fill subgrade under the loading of 200~400 km/h speed train is more than 3 mm above the current standard.The dynamic displacement of roadbed increases with the increase of vehicle speed,and decreases with the increase of depth.The variation amplitude of subgrade vertical acceleration increases with the increase of vehicle speed and decreases with the increase of horizontal distance.The higher the driving speed,the lower the attenuation rate of vertical acceleration.After treatment by CFG pile,the maximum settlement,dynamic displacement and vertical acceleration of soft rock fill subgrade are reduced,indicating that the dynamic characteristics of soft rock fill subgrade are improved after treatment by CFG pile.

关 键 词：铁路路基 行车速度 动位移 竖向加速度 

分 类 号：U213.1[交通运输工程—道路与铁道工程]