富水砂土地区明挖隧道基坑地下水控制技术研究  

Research on Groundwater Control Technology of Open-Cut Tunnel Foundation Pit in Water-Rich Sandy Soil Area

作　　者：余诚 周盛全 姚希磊 成泽林 汪海波[2] 刘芝东 贺世昌 YU Cheng;ZHOU Shengquan;YAO Xilei;CHENG Zelin;WANG Haibo;LIU Zhidong;HE Shichang(China Railway Siju Group Co.,Ltd.,Seventh Engineering Branch,Hefei 230022,China;Anhui University of Science and Technology,School of Civil Engineering and Architecture,Huainan 232001,China;Lunan High-Speed Railway Co.,Ltd.,Jinan 250014,China)

机构地区：[1]中铁四局集团有限公司第七工程分公司,安徽合肥230022 [2]安徽理工大学土木建筑学院,安徽淮南232001 [3]鲁南高速铁路有限公司,山东济南250014

出　　处：《河南科技》2024年第22期56-61,共6页Henan Science and Technology

基　　金：山东铁路投资控股集团有限公司2023年度科技计划项目(TTKJ2023-14)。

摘　　要：[目的]为研究复杂环境下基坑降水对明挖隧道施工带来的影响,确保施工过程安全可靠,通过分析地质条件,进行现场降水试验及数值模拟对施工方案进行分析。[方法]在现场降水试验数据基础上,利用ABAQUS软件建立适用于津维高铁济南联络线机场隧道项目的二维模型,对隧道基坑降水过程进行模拟,分析不同止水措施下止水效果及坑外土体的变形情况。将模拟结果与现场试验结果进行对比,证明所建立模型可适用于机场隧道基坑的降水设计。[结果](1)在砂土地层中,降水井采用3~7 mm滤料会造成降水井出水含沙量过大,改用粒径更小的粗砂后情况得到改善。(2)止水帷幕对止水帷幕外侧土体的侧向变形具有一定的抑制作用,越靠近止水帷幕变形抑制作用越明显。单独采用悬挂式止水帷幕时,土层最大侧向变形发生在止水帷幕以下的土层为1.63 mm,悬挂式止水帷幕+SMW工法桩时坑外最大侧向变形仍在止水帷幕底部出现,最大侧向变形为1.87 mm。(3)地连墙对土体变形具有抑制作用,但其长度对坑外土体变形的抑制作用有限。地下连续墙外侧土体在1.45倍的开挖深度处发生最大侧向变形,最大侧向变形为2.4 mm。[结论]悬挂式止水帷幕、悬挂式止水帷幕+SMW工法桩及地下连续墙均对土体变形具有抑制作用,且影响程度不同。[Purposes]In order to study the influence of foundation pit dewatering on open-cut tunnel con-struction in complex environment and ensure the safety and reliability of construction process,the con-struction scheme is analyzed by analyzing geological conditions,field dewatering test and numerical simulation.[Methods]A two-dimensional model suitable for the airport tunnel project of Jinan Connec-tion Line of Tianjin-Weifang High-speed Railway was established by using ABAQUS software on the ba-sis of the on-site dewatering test data.The dewatering process of tunnel foundation pit was simulated,and the effect of different dewatering measures under the tunnel and the soil deformation outside the pit were analyzed.By comparing the simulation results with the field test results,it is proved that the estab-lished model is suitable for the dewatering design of airport tunnel foundation pit.[Findings]①In the sandy soil formation,the use of 3~7 mm filter material in the dewatering well will cause the sediment content of the dewatering well to be too large,and the situation will be improved after the coarse sand with smaller particle size is used.②The impervious curtain has a certain inhibition effect on the lateral deformation of the soil outside the impervious curtain,and the closer the impervious curtain is,the more obvious the inhibition effect is.When the hanging suspended impervious curtain is used alone,the maxi-mum lateral deformation of soil layer occurs in the soil layer below the impervious curtain is 1.63 mm.When the suspended impervious curtain+SMW construction method,the maximum lateral deformation outside the pit still occurs at the bottom of impervious curtain,and the maximum lateral deformation is 1.87 mm.③the diaphragm wall has an inhibitory effect on soil deformation,but its length has a limited range of inhibition on soil deformation outside the pit.The maximum lateral deformation of the soil out-side the diaphragm wall occurs at 1.45 times the excavation depth,and the maximum lateral deformation is

关 键 词：富水砂土地区 基坑降水 现场试验 位移分析 Abaqus数值模拟 

分 类 号：U213[交通运输工程—道路与铁道工程]