摘要
针对河漫滩地质条件,运用数值分析方法,研究了欠压条件下分段推进盾构开挖面的稳定性。在考虑渗流的影响下,分析研究了不同埋深条件下的最小极限支护压力变化规律。结果表明:随着支护压力比的逐渐减小,隧道开挖面中心位移、塑性区、横向沉降、纵向沉降都要经历不敏感、较敏感和突变3个阶段;开挖面支护压力主要平衡的是地下水压力,水的影响不可忽视;在太原地铁2号线所考虑的区间,若最小极限支护压力比保持λ>0.4,开挖面前方则不会出现失稳状况;埋深对于最小极限支护压力比的影响不大。
Aiming at the geological conditions of floodplain,the stability of shield excavation surface with sublevel propulsion under the condition of underpressure was studied by using numerical analysis method.Considering the influence of seepage,the variation laws of the minimum limit support pressure under different buried depths were studied.The results showed that as the support pressure ratio gradually decreased,the center displacement,plastic zone,transverse settlement and longitudinal settlement of tunnel surface would undergo three stages of insensitivity,sensitivity and catastrophe.The main balance of support pressure on excavation surface was groundwater pressure,and the influence of water cannot be ignored.In the section of Taiyuan metro line 2,if the minimum limit support pressure was kept to be more than 0.4,the instability would not occur in front of the excavation surface,and the buried depth had little effect on the minimum limit support pressure ratio.
作者
郭子奇
杨双锁
郝瑞卿
赵智辉
鲍飞翔
罗百盛
GUO Ziqi;YANG Shuangsuo;HAO Ruiqing;ZHAO Zhihuix;BAO Feixiang;LUO Baisheng(College of Mining Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;China Railway No.3 Engineering Group Co.,Ltd,Taiyuan,Shanxi 030001,China)
出处
《矿业研究与开发》
CAS
北大核心
2019年第6期63-67,共5页
Mining Research and Development
基金
国家自然科学基金资助项目(U1710111)
山西省重点研发计划重点项目资助(201703D111027)
深部岩土力学与地下工程国家重点实验室基金资助项目(SKLGDUEX1820)
关键词
河漫滩地层
隧道开挖
欠压条件
分段推进
最小极限支护压力
Floodplain stratum
Tunnel excavation
Underpressure condition
Sublevel propulsion
Minimum limit support pressure
