邻近堆载作用下高铁桥基群桩承台水平位移控制研究  

Research on Horizontal Displacement Control of Group Pile Platform of High⁃speed Railway Bridge Under Adjacent Loading

作　　者：金国海 王震南 李友元 李平[2] JIN Guohai;WANG Zhennan;LI Youyuan;LI Ping(Hangzhou Local Railway Development Co.,Ltd.,Hangzhou,Zhejiang 310009,China;Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing,Jiangsu 210024,China;China Railway 24 Bureau Group Co.,Ltd.,Shanghai 200070,China)

机构地区：[1]杭州地方铁路开发有限公司,浙江杭州310009 [2]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210024 [3]中铁二十四局集团有限公司,上海200070

出　　处：《施工技术（中英文）》2022年第1期21-25,共5页Construction Technology

基　　金：国家自然科学基金(41977240);中央高校基本科研业务费项目(B200202090)。

摘　　要：结合沿海地区某新建邻近既有高铁的城际铁路试车线工程,对邻近堆载作用下既有高铁群桩承台水平位移的控制措施展开了分析。基于现场试验,利用PLAXIS3D建立有限元模型,探讨了隔离桩和在堆载面下进行水泥土加固两种形式对群桩承台水平位移控制效率的影响。研究结果表明:当采用单排隔离桩时,随隔离距离的增加隔离效率迅速下降,在有效距离范围内随着隔离桩深度的增加隔离效率逐步增大,存在峰值现象;双排隔离桩比单排桩具有更好的控制作用,而双排桩的排布形式影响较小;对堆载面下进行水泥土加固,在相同置换率情况下,“中间形”的加固形式效果较好;采用水泥土+隔离桩组合下的水平位移控制效率η提高幅度更为显著。Combined with a new intercity railway test project in a coastal area,the control measures of horizontal displacement of pile group platform of the existing high⁃speed railway under the action of adjacent loading are analyzed.Based on the field tests,finite element numerical model established by PLAXIS^(3D),the effects of isolation pile and cement⁃soil reinforcement under the load surface on the horizontal displacement control efficiency of pile group platform are discussed.The results show that when single⁃row isolation pile is used,the isolation efficiency decreases rapidly with the increase of isolation distance,and increases gradually with the increase of isolation pile depth within the range of effective distance,with a peak phenomenon.Double⁃row isolation pile has better control effect than single⁃row isolation pile,but the arrangement of double⁃row isolated pile has less influence.When cement⁃soil reinforcement is carried out under the loading surface,under the condition of the same replacement rate,the“intermediate type”reinforcement has a better effect.The control efficiencyηof horizontal displacement under the combination of cement soil and isolation pile is improved significantly.

关 键 词：高铁 桥基 邻近堆载 隔离桩 水泥土加固 变形 控制 

分 类 号：TU753.3[建筑科学—建筑技术科学]