摘要
针对沪昆铁路刘家庄隧道穿越煤系地层施工中发生的大变形现象,基于理论分析、数值模拟和现场监测方法,分析隧道发生大变形的原因,推导并验证了产生大变形的起始位置,得到了掌子面上方煤层单元体沿倾斜面方向的应力状态与隧道进入含倾斜煤系地层水平距离之间的变化规律,对倾斜煤层单元体与初期支护结构的应力与变形进行了分析。结果表明:掌子面上方煤体单元应力状态变化随掌子面进入倾斜煤层下方水平距离的增加,围岩经历挤压、压剪和剪切滑移3个变形阶段。围岩大变形与初期支护结构破坏均发生在剪切滑移阶段的初期,应在压剪变形阶段结合现场监测数据对掌子面进行喷射混凝土封闭、注浆加固掌子面上方松散煤层和加强初期支护结构刚度等措施以预防隧道产生大变形。
For Liujiazhuang railway tunnel of Shanghai-Kunming through the coal strata in construction of large deformation phenomenon,based on theoretical analysis,numerical simulation and field monitoring method,this study investigates the causes of significant deformation in tunnels,focusing on the initial locations of this deformation.It examines the impact of stress states on unit cells aligned with the inclined direction of a coal seam and explores the relationship between tunnel depth and horizontal distance in tilted strata.Additionally,the research analyses the stress and deformation experienced by the element body and the primary support structures in an inclined coal seam.The result showed that the stress state of the coal element above the palm face increases with the horizontal distance between the palm face and the bottom of the inclined coal seam,and the rock mass is subjected to three deformation stages including extrusion,compression shear and shear slip.The large deformation of surrounding rock and the failure of primary support structure both occur in the early stage of shear slip stage,so shotcreting to palm face,grouting reinforcement to coal seam up the palm face and strengthening the stiffness of primary support should be taken to prevent the large deformation of the tunnel in the stage of compression and shear deformation combined with the field monitoring data.
作者
康宝祥
宋战平
张庆贺
许晓静
周冠南
潘红伟
KANG Baoxiang;SONG Zhanping;ZHANG Qinghe;XU Xiaojing;ZHOU Guannan;PAN Hongwei(School of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,P.R.China;Key Laboratory of Rock and Underground Space Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,P.R.China;Institute of Tunnel and Underground Structure Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,P.R.China;School of Architectural Engineering,Xuzhou College of Industrial Technology,Xuzhou 221000,Jiangsu,P.R.China;China Railway Construction Bridge Engineering Group Co.,Ltd.,Tianjin 300300,P.R.China;China Railway Beijing Engineering Bureau Group First Engineering Co.,Ltd.,Xi'an 710100,P.R.China)
出处
《土木与环境工程学报（中英文）》
CSCD
北大核心
2024年第2期89-99,共11页
Journal of Civil and Environmental Engineering
基金
国家自然科学基金(52178393)
陕西省创新能力支撑计划-创新团队(2020TD-005)。
关键词
隧道工程
煤系地层
围岩大变形
破坏机理
数值模拟
tunnel engineering
coal strata
large deformation of surrounding rock
failure mechanism
numerical simulation
