变质岩区隧道开挖作用下围岩应力场变化及其稳定性分析  

Stress Field Variation and Stability Analysis of Surrounding Rocks in Excavation of Metamorphic Rock Tunnel

作　　者：周潇朗 张常亮[1] 乔朋腾 ZHOU Xiao-lang;ZHANG Chang-liang;QIAO Peng-teng(School of Geology Engineering and Geomantics,Chang an University,Xi an 710054,Shaanxi,China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054

出　　处：《地球科学与环境学报》2018年第4期497-504,共8页Journal of Earth Sciences and Environment

基　　金：陕西省自然科学基础研究计划项目(2016JM4018);国家重点基础研究发展计划("九七三"计划)项目(2014CB744701);中国地质调查局地质调查项目(121201011000150018)

摘　　要：为研究复杂工程地质条件下的隧道围岩在施工过程中的力学特征,以陕西省石泉县喜河—后柳改建公路的拟建隧道为研究对象,以有限元为研究方法,基于其地形地貌、地层岩性、水文地质等工程地质特征数据,形成模型相关参数,以此建立隧道三维地质数值分析模型,利用隧道钝化模拟单向全断面开挖的施工工况,探讨其应力分布特征及变化规律。结果表明:开挖的隧道会表现出显著的应力集中现象,其对隧道顶部围岩稳定性影响最大;在本模型中,隧道开挖未支护时,天然应力处于临界状态的中风化绿泥石石英片岩和断层带整体处于破坏的应力状态,而开挖前相当稳定的微风化绿泥石石英片岩、微风化石灰岩、微风化闪长岩在开挖时大部分处于稳定状态,只有局部处于破坏状态,而微风化碳质石英片岩稳定性不受影响;在参考监测数据中,中风化绿泥石石英片岩开挖后失稳,其他岩层处于稳定状态。In order to study the mechanical characteristics of tunnel surrounding rock during construction in complex engineering geological conditions,taking the proposed tunnel of Xihe-Houliu rebuild highway in Shiquan county of Shaanxi province as the research object,taking finite element as the research method,based on the data of topography,stratum lithology,hydrogeology and other engineering geological characteristics,the model related parameters were formed,and the tunnel three-dimensional geological numerical analysis model was established;the construction condition of one-way full-face excavation was simulated by tunnel passivation were formed,and the stress distribution characteristics and variation were studied.The results show that the excavated tunnel exhibits significant stress concentration,which brings the greatest impact on the top of the tunnel;when the excavated tunnel is not supported,the middle weathering chlorite quartz schist and the fault zone,in which the natural stress is in a critical state,are in a destructive stress state;the weak weathering chlorite quartz schist is quite stable before excavation,the same is true for weak weathering limestone and weak weathering diorite,and most of them are in a stable state with partial destruction after excavation;the stability of weak weathering carbonaceous quartz schist is not affected;in the reference monitoring data,the middle weathering chlorite quartz schist is unstable after excavation,and other strata are stable.

关 键 词：隧道工程 围岩 断层带 侵入体 应力 有限元 数值模拟 全断面开挖 

分 类 号：P642.4[天文地球—工程地质学] TU931[天文地球—地质矿产勘探]