浅埋大偏压隧道洞口联合支护方案及稳定性分析  

Joint support scheme of shallow-buried tunnel entrance with large bias pressure and its stability analysis

作　　者：唐咸远 吴尉靖 温科浩 唐瞻鹏 TANG Xianyuan;WU Weijing;WEN Kehao;TANG Zhanpeng(School of Architecture and Traffic Engineering,Guilin University of Electronic Technology,Guilin 541004,China;Guangxi Guitong Engineering Management Group Co.,Ltd.,Nanning 530029,China)

机构地区：[1]桂林电子科技大学建筑与交通工程学院,广西桂林541004 [2]广西桂通工程管理集团有限公司,广西南宁530029

出　　处：《广西科技大学学报》2024年第4期44-50,共7页Journal of Guangxi University of Science and Technology

基　　金：国家自然科学基金项目(42067044);广西研究生教育创新计划项目(YCSW2021171)资助。

摘　　要：云盘隧道洞口段存在浅埋偏压、半明半暗、山体陡峭等不利条件,施工难度极大。为保证隧道洞口稳定,确保进洞施工安全,根据地质勘测报告及地形特点,提出抗滑桩+挡墙+锚索等联合支护方案及合理的施工方法;采用有限元软件建立三维模型,分析洞口段围岩与支护结构的位移及应力,并结合现场监测数据,验证了支护效果。结果表明:X、Z方向的位移最大值分别约为20.04、18.74 mm,均处于设计预留变形量范围内;隧道初期支护最大拉、压应力分别约为1.22、3.99 MPa,均低于C30混凝土的轴心抗拉、抗压强度设计值,表明支护受力较为合理;隧道现场监测拱顶累计沉降值为16.90 mm,断面周边收敛值为17.70 mm,与计算值相近,表明采用抗滑桩+挡墙+锚索等联合支护可有效控制隧道围岩位移和初期支护应力变化,应用效果良好。There were adverse conditions such as shallow-buried tunnel entrance with large bias pressure,semi-dark and semi-light,steep mountains in Yunpan Tunnel.So the construction was extremely difficult.To ensure the stability of the tunnel entrance and the safety of the construction,a joint support scheme and construction methods of anti-slide pile+retaining wall+anchor cable were proposed according to the geological survey report and terrain characteristics.Then,the threedimensional model was established by using finite element software.And the displacement and stress of surrounding rock and supporting structure of the entrance section were analyzed.Finally,the supporting effect was verified combining field monitoring data.The results show that the maximum displacement values of X direction and Z direction were about 20.04 mm and 18.74 mm respectively,which were both within the range of reserved deformation;The maximum tensile and compressive stresses of the initial support of the tunnel were about 1.22 MPa and 3.99 MPa respectively,which were lower than the design values of the axial tensile and compressive strength of C30 concrete,indicating that the support force is reasonable.The cumulative settlement value of the arch roof monitored on site was 16.90 mm;The convergence value around the section was 17.70 mm,which were in agreement with the calculated values,indicating that the proposed joint support scheme can effectively control the displacement of tunnel surrounding rock and the change of initial support stress,and the application effect is good.

关 键 词：隧道工程 浅埋偏压 洞口施工 数值分析 现场监测 

分 类 号：U453.1[建筑科学—桥梁与隧道工程]