摘要
为研究隧道下穿煤层采空区影响下围岩变形和支护构件受力规律,以郑(州)-太(原)高速铁路太(原)-焦(作)段控制性工程——皇后岭隧道为工程背景,开展数值分析以及现场监测,对比隧道常规段、下穿采空区段围岩位移、拱架受力以及围岩接触压力。结果表明:采空区对隧道围岩位移存在一个高度影响范围,约1.81~2.29倍的隧道洞径;上、中、下台阶开挖引起的拱顶位移比重为6∶2∶2,上台阶开挖属于重点监控时期;围岩变形的稳定时间为35~40 d。拱架整体受压,下穿采空区段拱架轴力均值约为常规段拱架的2倍,轴力分布离散率约为常规段拱架的5倍。下穿采空区段拱架轴力分布非对称显著,拱顶为承担围岩压力的关键部位;常规段拱架轴力整体分布均匀性良好。下穿采空区段围岩接触压力非对称现象显著,常规段围岩接触压力近似对称分布。围岩接触压力均值变化规律不同,稳定后大小基本相同。下穿采空区段围岩接触压力分布离散率约为常规段的1.5倍。常规段围岩接触压力分布形态先于拱架轴力保持稳定,隧道下穿采空区段的情况则相反。研究结果为隧道穿越采空区围岩稳定性分析提供了参考。
To clarify the law of surrounding rock deformation and force change of support components under the influence of tunnel passing through coal mine goaf,the Taiyuan-Jiaozuo section of Zhengzhou-Taiyuan high speed railway control project-Huanghouling Tunnel is taken as the engineering background.Numerical analysis and field monitoring were carried out to compare the displacement of surrounding rock,arch force and contact pressure of surrounding rock in the conventional section and the underpass goaf section of the tunnel.The results show that:There exists a height influence range for the goaf on the surrounding rock of the tunnel,which is about 1.81~2.29 times of the tunnel diameter.The proportion of displacement caused by the excavation of upper,middle and lower benches is 6∶2∶2,thus the excavation of the upper bench is a key monitoring period.The stability time of surrounding rock is 35~40 days within the influence height range of goaf.The arch of the tunnel underpass goaf is compressed as a whole,the average axial force of the arch in the section under the goaf is about 2 times of that in the conventional section,and the dispersion rate of axial force distribution is about 5 times of the conventional arch.The axial force distribution of the arch in the section under the goaf is asymmetric,and the arch roof is the key part to bear the surrounding rock pressure;the distribution uniformity of axial force of conventional arch is good.The contact pressure asymmetry of surrounding rock in the goaf section is obvious,the contact pressure of surrounding rock in conventional section is approximately symmetrical.The average value of contact pressure of surrounding rock is different,and the value is basically the same after stabilization.The dispersion rate of contact pressure distribution of surrounding rock in the section under goaf is about 1.5 times of that in the conventional section.The distribution of contact pressure in the conventional section of the tunnel is stable prior to the axial force of the arch,while t
作者
潘锐
杜文正
程桦
蔡毅
叶中豹
陈平
安刚建
PAN Rui;DU Wenzheng;CHENG Hua;CAI Yi;YE Zhongbao;CHEN Ping;AN Gangjian(Anhui Province Key Laboratory of Building Structure and Underground Engineering,Anhui Jianzhu University,Hefei,Anhui230601,China;Anhui Province Engineering Technology Research Center of Urban Construction and Underground Space,Anhui Jianzhu University,Hefei,Anhui230601,China;China Railway No.4 Engineering Group Co Ltd,Hefei,Anhui230012,China;The Fourth Engineering Co Ltd,China RailwayNo.4Engineering Group Co Ltd,Hefei,Anhui 230012,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2022年第5期901-910,920,共11页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51904006)
安徽省重点研究与开发计划项目(202104a07020019)
安徽省自然科学基金项目(2108085QD169)
安徽省高校自然科学重点项目(KJ2019A0745)
安徽建筑大学建筑结构与地下工程安徽省重点实验室开放课题项目(KLBSUE-2021-02)。
关键词
隧道
下穿采空区
初期支护
评价指标
围岩变形
拱架受力
tunnel
undercrossing goaf
initial support
evaluating indicator
surrounding rock deformation
arch force
