浅埋隧道双侧壁导坑法施工数值模拟研究  

Numerical simulation study on construction method of double side-wall diversion for shallow buried tunnels

作　　者：徐运明[1] 欧阳文利 陈维超 XU Yunming;OUYANG Wenli;CHEN Weichao(Department of Architectural Engineering,Hunan Urban Construction College,Xiangtan 411104,China;Hunan Construction Senior Technical School,Changsha 410015,China;Hunan No.4 Engineering Co.,Ltd.,Changsha 410119,China)

机构地区：[1]湖南城建职业技术学院建筑工程系,湖南湘潭411104 [2]湖南建筑高级技工学校,湖南长沙410015 [3]湖南省第四工程有限公司,湖南长沙410119

出　　处：《水利水电快报》2024年第9期51-57,共7页Express Water Resources & Hydropower Information

基　　金：湖南建工集团科技计划重大专项(JGJT2019-09);湖南省建设厅科学研究项目(KY202206)。

摘　　要：为准确评价浅埋隧道施工过程的围岩稳定性,利用ANSYS有限元数值分析软件,对沈阳地铁10号线区间浅埋隧道双侧壁导坑法施工进行数值模拟,研究了浅埋隧道施工过程的力学特性及变形规律。结果表明:开挖中上导洞后,围岩位移、应力和支护结构内力显著增大,占整个导洞开挖的50%,且最大位移、应力和支护结构弯矩集中在拱顶、初期支护连接的薄弱处;地表沉降量随时间变化增长趋缓,开挖90 d后趋于稳定,且离开挖面越近,沉降量越大,最大沉降点出现在最先开挖的中上导洞位置;隧道开挖10 d内拱顶下沉较快,随开挖掌子面远离监测点,拱顶沉降速率逐渐减小,开挖顺序对拱顶沉降影响较大,往往先开挖的位置拱顶沉降最大。现场监测结果表明:数值计算与现场监测结果比较吻合,验证了数值分析的合理性。研究成果对浅埋隧道的安全、经济施工具有借鉴意义。In order to properly estimate the surrounding rock stability in the building process of shallow buried tunnel,we used ANSYS finite element numerical analysis software to conduct numerical simulation of double-side diversion method construction of shallow buried tunnel in the section of Shenyang Metro Line 10,and analyzed the mechanical features and deformation law of shallow buried tunnel construction process.The results showed that after excavating the upper guide tunnel,the displacement,stress,and internal force of the surrounding rock and supporting structure increased dramatically,accounting for 50%of the total guide tunnel excavation,and the highest displacement,stress,and bending moment of the supporting structure concentrated on the weak connection of the arch and the initial support.The increase in surface settlement over time slowed down and reached a stable state after 90 days after excavation.The settlement increased with the distance from the excavation surface,and the maximum settlement point was at the middle and upper guide tunnels where the dug was out first.The vault subsidence sinks rapidly within 10 days of tunnel excavation and then the subsidence rate gradually reduced as the excavation face moved away from the monitoring site.The vault settlement was greatly influenced by the excavation order,and the vault settlement was typically highest at the initial excavation site.The on-site monitoring results showed that the numerical analysis in the study was reasonable based on the field monitoring data,which was in good agreement with the numerical calculation.The results can provide a reference for the safety and economics of shallow buried tunnel construction.

关 键 词：浅埋隧道 双侧壁导坑法 力学特性 数值模拟 现场监测 沈阳地铁 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]