不同基床底层细颗粒含量的高速铁路路基水分运移规律及水囊控制  

Moisture Migration and Saturation Zone Control of High-speed Railway Track-bed with SBL of Different Fines Content

作　　者：王瀚霖 陈仁朋[1,3] 程威 WANG Hanlin;CHEN Renpeng;CHENG Wei(College of Civil Engineering,Hunan University,Changsha 410082,China;Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong 999077,China;Institute of Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]香港理工大学土木及环境工程学系,香港999077 [3]浙江大学岩土工程研究所,浙江杭州310058

出　　处：《铁道学报》2020年第9期150-156,共7页Journal of the China Railway Society

基　　金：国家自然科学基金(41472244,U1234204)。

摘　　要：通过数值方法建立了高速铁路路基渗流模型,其由上部结构和基床表层、基床底层、地基组成。在左线底座与基床表层交界处设置两条裂缝模拟降雨入渗边界,对模型施加2013年杭州市降雨数据进行3 a计算,分析了基床底层不同细颗粒含量对路基内部水分运移的影响。研究表明,3 a计算时间后,各工况路基内部均出现水囊,且随着细颗粒含量增大,水囊面积增大。湿润锋击穿基床表层和基床底层交界面的时间、到达基床底部的时间均随细颗粒含量的增大而增大。最后,在基床表层和基床底层之间增设一层渗透系数较低的GCL复合垫层,并结合在基床表层和基床底层之间设置毛细屏障的现场试验,探讨了水囊控制方法。In this study,a numerical model for the track-bed of high-speed railway was built,consisting of superstructure,subgrade surface layer(SSL),subgrade bottom layer(SBL),and subsoil.Two fissures were set at the edges between the left-line concrete base and SSL,to simulate the infiltration boundary.The rainfall data of Hangzhou in 2013 was applied and repeated for a 3-year calculation on each model and the effects of fines content of SBL on the moisture migration inside the subgrade were investigated.The results show that saturation zone develops in the subgrade in all cases,with the saturation zone size increasing as fines content increases.The time for the wetting front to penetrate the interface between SSL and SBL and the time for the wetting front to migrate to the bottom of SBL both increase with the increase of fines content.Finally,in combination with the setup of a geosynthetic clay liner(GCL)with a low infiltration coefficient between SSL and SBL and some field infiltration tests of a subgrade installed with the wicking fabric,it is indicated that the GCL or wicking fabric both succeed to effectively control the saturation zone.

关 键 词：水分运移 高速铁路 细颗粒含量 水囊 GCL复合垫层 毛细屏障 

分 类 号：TV139.14[水利工程—水力学及河流动力学]