【作者】 张鹏；

【导师】 徐华；

【作者基本信息】 西南交通大学 ， 建筑与土木工程（专业学位）， 2019， 硕士

【摘要】 山岭隧道施工时常会遇到突涌水灾害,严重威胁施工安全,如何对突涌水灾害提前进行风险评估及防控是隧道工程中面临的难点问题。论文通过对隧道已发生突涌水灾害的案例分析,进行山岭隧道突涌水评估及防治措施研究。以典型山岭隧道的突涌水段为工程依托,综合利用现场调研、测试、数值模拟等多种手段,分析了突涌水的原因及机理,提出了相应的处治措施。研究成果不仅对依托隧道的突涌水防治提出了建议,还可以为同类隧道提供参考。取得的主要研究成果如下:(1)通过案例收集和现场调研,分析了30余座典型山岭隧道突涌水灾害的基本情况、形成机理及处治措施,提出了突涌水主要受地质构造、地层岩性、水力条件的影响,并重点考虑了施工期间的施工因素对突涌水的影响。利用模糊综合评判方法的模型作为隧道突涌水风险评估模型,选取了地质构造、地层岩性、水力条件和施工因素作为一级指标,并采用突涌水灾害有关的16个影响因素作为二级指标,建立模糊层次模型。通过风险矩阵法确定隧道突涌水的风险等级,利用层次分析法确定影响因素的权重,建立了一套较为完整的山岭隧道突涌水风险评估模型。(2)依据山岭隧道突涌水风险评估提出的突涌水风险等级,并结合隧道突涌水灾害的主要防控措施,提出了不同风险级别的突涌水防控措施建议。同时根据隧道现场突涌水量的大小和形成原因,提出了相应的处治措施建议。(3)以典型山岭隧道突涌水段为依托,对突涌水段进行风险评估,结果显示该段处于高风险中。通过对现场的水文地质、突涌水特点、围岩结构特征的调查,对隧道突涌水的原因及机理进行了分析,依据突涌水段的具体特征,提出了“排堵结合,限量排放”的综合处治方案。(4)针对典型山岭隧道的突涌水灾害处治措施,运用FLAC3D有限差分软件,开展三维数值模拟计算,研究隧道围岩在开挖和支护过程中的稳定性以及支护结构的特征,通过布点监测,对比了不同工况下“径向注浆封堵”措施对监测断面的位移变化规律,采取合理的“径向注浆封堵”措施,结果显示在隧道开挖至监测断面后围岩较早地进入稳定平衡状态。更多还原

【Abstract】 Water inrush geological disasters are often encountered in the construction of mountain tunnel,which seriously threaten the construction safety.How to carry out risk assessment and control of water inrush disasters in advance is the key and difficult problem in the construction of tunnel engineering.The study on evaluation and prevention and control measures of sudden water inrush in mountain tunnel is helpful to reduce the occurrence probability and loss of sudden water inrush.Based on the FeiXianGuan tunnel project.By means of field investigation and numerical simulation,the causes and mechanism of water inrush disasters in tunnel are studied,and the corresponding prevention measures are put forward.The results not only provide some Suggestions for preventing sudden water gushing in FeXianGuan tunnel,but also provide some references for similar tunnels.The results obtained in this paper are as follows:(1)Through case collection and field investigation,this paper analyzes the basic situation,formation mechanism and treatment measures of typical mountain tunnel water bursting disaster,and summarizes that water bursting disaster is mainly affected by geological structure,stratum lithology,water conservancy conditions and construction factors.On the basis of analyzing the advantages and disadvantages of the traditional evaluation system,evaluation method and calculation model,the mathematical model of two-level fuzzy comprehensive evaluation method is selected as the risk evaluation model of tunnel surge water.Selected the geologic structure,stratum lithology,hydraulic conditions and construction factors as the primary index,forming a sudden surge of water disaster on 16 factors as the secondary impact factor,fuzzy hierarchy structure model is established,the analytic hierarchy process(ahp)is used to determine the weight of the impact factor,then according to the risk matrix method to determine the risk level,set up a complete set of mountain tunnel water risk assessment model.(2)Based on the risk grade of sudden water inrush put forward in the risk assessment of tunnel water inrush,and combined with the main prevention measures of tunnel water inrush disaster,the corresponding risk level of sudden water inrush prevention measures system is developed.At the same time,according to the size and cause of the water inrush in the construction site,corresponding treatment measures are put forward.(3)Based on typical tunnel,the risk assessment of sudden inrush section shows that it is in high risk.Based on the investigation of hydrogeological conditions,hydrodynamic characteristics of water gushing and surrounding rock structure characteristics of the tunnel with field exploration and measured data,this paper analyzes the origin mechanism and basic characteristics of the sudden water inrush in FeiXianGuan tunnel,and puts forward the treatment scheme of "combination of drainage and blocking,limited discharge" according to the specific characteristics of the sudden water inrush section of the tunnel.(4)Using FLAC3 D finite element software to carry out the three-dimensional numerical simulation,studied the stability of surrounding rock in excavation and supporting process and the characteristics of the stress of the supporting structure,the displacement change rule of "radial grouting plugging" measure to the monitored section is compared through the measurement of location,and the measure of "radial grouting plugging" is adopted to ensure that the surrounding rock enters a stable equilibrium state early after the tunnel excavation reaches the monitored section.更多还原