摘要
为分析盾构隧道施工期各因素对管片上浮错台的影响,基于盾构隧道施工期的受力模式拟定了隧道直径、围岩条件、覆土厚度、浆液凝固时间、浆液密度、盾构掘进速度及盾尾间隙等7个主要影响因素,分别建立了盾构隧道施工期上浮分析模型与管片错台量计算模型,分析了施工期各因素影响下盾构隧道上浮错台量的变化规律。进一步地,结合现场监测试验结果,验证了施工期管片上浮错台的现象与规律,得出主要结论如下:①地层刚度减弱、浆液密度增大、浆液凝固时间增长、隧道埋深减小、隧道掘进速度提高、盾尾间隙增大及浆液凝固后刚度减小将加剧施工期管片的上浮错台。②隧道直径增大使管片上浮量增大,但与管片错台量的相关性不大。③管片上浮时,管片环间接触摩擦与环间螺栓将起到抗剪作用,控制错台的发展。④减小浆液浮力、增大管片环间连接刚度、增强地层约束、缩短流体段长度可减小施工期管片上浮错台。⑤提出计算错台量的方法可对管片接缝防水设计提供依据。
In order to analyze the influences of various factors during the construction period of a shield tunnel on the uplifting dislocation of segments,seven influencing factors are proposed according to the mechanical state,including outer diameter of the tunnel,ground condition,cover depth,coagulation time and density of synchronous grouts,shield tunneling speed and shield tail clearance.Numerical models for tunnel uplifting and segment dislocation are established to investigate the dislocation under different influencing factors.Then the variation laws of the segment dislocation are analyzed under the influences of various factors during the construction period.Moreover,the phenomenon and laws of the segment dislocation during shield tunnelling are verified through the test results of on-site monitoring.The main conclusions are as follows:(1)The segment dislocation will be intensified when the ground stiffness weakens,the density of synchronous grout increases,the coagulation time of synchronous grouts grows,the cover depth decreases,the tunneling speed increases,the shield tail clearance increases,and the grout stiffness after solidification decreases.(2)The increase of the tunnel diameter will lead to the increase of the segment uplifting,but has little correlation with the segment dislocation.(3)When the segment is uplifting,the contact friction between the segment rings and the bolt between the rings will play the role of shear resistance to control the dislocation.(4)Decreasing the uplifting force of the grouts,increasing the connection stiffness between the segments and the rings,strengthening the formation constraint and shortening the length of the fluid segment can reduce the segment uplifting dislocation during construction.(5)The proposed method to calculate the amount of dislocation can be used as a reference for the longitudinal waterproof design of segments.
作者
肖明清
封坤
周子扬
刘伊腾
鲁志鹏
XIAO Mingqing;FENG Kun;ZHOU Ziyang;LIU Yiteng;LU Zhipeng(China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China;Hubei Provincial Engineering Laboratory for Underwater Tunnel,Wuhan 430063,China;Key Laboratory of Transportation Tunnel Engineering of Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2023年第7期1347-1356,共10页
Chinese Journal of Geotechnical Engineering
基金
国家重点研发计划项目(2021YFB2600900)
国家自然科学基金项目(52078430,51878569)。
关键词
盾构隧道
管片衬砌
同步注浆
隧道上浮
环间错台
shield tunnel
segment lining
synchronous grouting
tunnel uplifting
segment ring dislocation
