湖北某隧道岩溶水文地质条件探讨

本隧道隧址区构造强烈,断层发育,是望佛山—聚龙山复式倒转向斜的西段部分。由于隧址区大量出露寒武系可溶岩地层,岩溶发育,对隧道安全建设存在很大影响。通过对隧址区岩溶发育和地下水径流规律的研究,划分相应的岩溶水文地质单元,探讨不同单元岩溶地下水的径流路径及其与隧道之间的关系,研究结果表明,岩溶地层内岩溶发育,洼地、落水洞和溶洞等溶蚀现象大量存在,地下水交替极快,补给来源广,渗流途径通畅,隧址区有岩溶大泉形成。     

南川黄泥垭隧道工程对水文地质条件的影响分析

隧道工程建设无疑对岩溶地区的水文地质环境地质带来巨大冲击。文章以重庆市南川区黄泥垭隧道工程为实例,采用地面调查、示踪试验、长观监测等方法进行综合研究,剖析隧道工程对隧址区水文地质环境的影响。研究结果表明:黄泥垭隧道工程改变了隧址区的地下水流场,疏干地表地下水、加剧干旱缺水程度,并随之出现新的人工水点——隧道涌水;同时隧道工程影响了水资源空间分配格局、降低了水资源利用率。      

山区公路隧道建设对地下水环境扰动评价研究

由于长大隧道建设期间具有显著地集水廊道效应,施工过程中地下水不断向隧道轴线汇集,进而诱发一系列的水文 地质灾害,给施工人员和隧址区周边的生态环境带来不可估量的损失。为此,在构建山区公路隧道建设对地下水环境扰动 评价体系的基础上,考虑到群决策不同个体实践认知水平的差异,把基于决策人员偏好信息的区间数层次分析模型用于山 区公路隧道建设对地下水的环境影响评价领域,并与模糊综合评判法进行有机结合,对西藏米拉山特长隧道建设对地下水 环境影响进行评价,结果表明,米拉山特长公路隧道建设对地下水的扰动程度属于一般水平。依据评价结果,采取了相 应的工程措施,实现了隧道建设与隧址区环境保护的协调统一,可为类似地区隧道建设的地下水环评工作提供有益的 参考。     

黄土梁隧道对自然保护区地下水环境的影响及防治措施

隧道工程的建设对自然保护区的地下水环境影响问题是值得关注的重大问题,本文通过对黄土梁隧道隧址区的地下水环境现状及水文地质条件的调查,初步判定隧道建设对地下水环境的影响主要为涌突水、渗漏水及地下水水质恶化对自然保护区的影响,提出了相应的防治措施。     

山区公路隧道建设对地下水环境扰动评价研究

由于长大隧道建设期间具有显著地集水廊道效应，施工过程中地下水不断向隧道轴线汇集，进而诱发一系列的水文 地质灾害，给施工人员和隧址区周边的生态环境带来不可估量的损失。为此，在构建山区公路隧道建设对地下水环境扰动 评价体系的基础上，考虑到群决策不同个体实践认知水平的差异，把基于决策人员偏好信息的区间数层次分析模型用于山 区公路隧道建设对地下水的环境影响评价领域，并与模糊综合评判法进行有机结合，对西藏米拉山特长隧道建设对地下水 环境影响进行评价，结果表明，米拉山特长公路隧道建设对地下水的扰动程度属于一般水平。依据评价结果，采取了相 应的工程措施，实现了隧道建设与隧址区环境保护的协调统一，可为类似地区隧道建设的地下水环评工作提供有益的 参考。     

海东隧洞施工过程中地下水动态变化预测

以海东隧洞萂村段为例,从隧址区地质概况入手,在地下水补给、径流和排泄规律宏观掌握的基础上,运用Visual MODFLOW地下水三维数值模拟软件对隧址区地下水动态变化进行预测分析。结果表明:随着隧洞施工的推进,隧址区天然渗流场逐渐受到干扰,水位逐渐降低,形成地下水降落漏斗,漏斗范围不断扩大,影响范围达7.52 m。部分区域会发生地下水疏干现象,从而对周边地下水环境造成影响,影响到当地居民的生产生活用水。     

青海天峻新关角隧道涌排水水源识别与量化分析

涌排水严重影响隧道施工与运行安全,查明隧道涌排水的来源,是隧道防水止水重要科学依据.青海天峻新关角隧道南北洞口处的地下水排水量分别为10021,60877 m3/d,两者存在近50000 m3/d的差异,涌排水量大,且来源不明.基于水文地质条件分析,分别采集了新关角隧道隧址区内大气降水、不同类型地下水和隧道出口涌排水水...     

大坪隧道水文地质条件分析及涌水量预测

大坪隧道地处秦岭南麓中山区,为引汉济渭工程中三河口水利枢纽至黄金峡水电枢纽控制性工程之一,地层及构造较为复杂,通过水文地质综合调查方法,分析隧址区水文地质条件,采用地下水径流模数法及地下水动力学法对隧道涌水量进行预测计算,预测结果表明隧道较大涌水点主要集中在断裂构造密集带及灰岩溶隙发育区段,进而为隧道施工提出建议。     

成都国际会展中心输气管线府河穿越隧道涌水量预测

成都拟建国际会展中心供气工程府河输气隧道在府河河底以下40m,采用“竖井＋隧道＋竖井”方案。隧址位于府河及其Ⅰ级阶地,隧道涌水问题严重。为保证施工、运营的安全,在分析隧址区水文地质条件的基础上,对隧道涌水做出初步预测评价,为施工提供依据.     

贵州某隧道岩溶水文地质条件及涌水量研究

拟建隧道位于贵州岩溶地区,地质条件复杂,且隧道将横穿过一条地下河下方,隧道遭遇岩溶涌突水的危险性较大。通过分析该隧道岩溶水文地质环境,论述了隧址区岩溶发育分布规律、岩溶水补径排条件,并采用地下水径流模数法和大气降水入渗法2种方法对比计算对隧道涌水量做出初步预测评价,为施工提供依据。     

国道213线五指山隧址区水文地球化学特征研究

运用水文地球化学方法对国道213线五指山隧道进行研究。涌水起源和地下水循环特征等方面的研究。结果表明:国道213线五指山隧道涌水属于深循环地下水,进口段隧道涌水主要来自于砂页岩含水层,而隧道出口段涌水化学组成则受控于石膏矿物的溶解;硫、氧同位素组成分析证实五指山隧道主要涌水带均与浅表地下水的直接下渗有关。此研究成果为隧道涌突水的预防和治理提供了理论依据。     

Application of fuzzy Delphi AHP method for the estimation and classification of Ghomrud tunnel from groundwater flow hazard

Water inflow and water pressure controls are needed in the design, construction, and exploitation of tunnels. The objective of this paper is to present a new system which can be appropriate for rating tunnel sites to evaluate the potential of groundwater inflow according to the preliminary site investigation data. In this paper, an evaluation model based on combining the analytic hierarchy process and the fuzzy Delphi method has been presented for assessing tunnel site rating from the groundwater hazard point of view. This research treats the tunnel site classification as a group decision problem and applies the fuzzy logic theory as the criterion to calculate the weighting factors. Afterward, the proposed method was successfully applied to determine the amount of groundwater inflow into tunnels. Results of several case studies in various geological conditions roughly show that it can be used to determine the groundwater inflow into tunnels. The introduced method has been examined successfully in Ghomroud tunnel. Results from the proposed method, analytical equations, and observed groundwater inflow into Ghomrud tunnel have been compared. Results show that, because most of parameters regulating groundwater inflow into tunnels have been considered in the method, results from the method are very close to the observed groundwater inflow. Applying this method, according to preliminary investigations conducted by the designers, provides a more suitable design of the drainage system, drilling method, and tunnel support.     

地下水多元示踪试验在岩溶隧道水害预测中的应用——以张吉怀高铁兰花隧道为例

以张家界—吉首—怀化高速铁路兰花隧道为例,在岩溶水文地质调查基础上结合地下水多元示踪技术,查明了兰花隧道隧址区各岩溶地下水系统以及地下暗河管道的空间展布。结果表明:（1）兰花隧道及其附近区域全部为寒武系碳酸盐岩裸露区,以峰丛洼地为主,地表和地下岩溶极为发育;（2）兰花隧道隧址及其附近区域共发育有呆业洞和兰花洞两个独立的地下暗河系统,其中Ⅰ号、Ⅱ号、Ⅲ号三个岩溶水系统属于兰花洞地下暗河系统的子系统;Ⅳ号岩溶水系统属于呆业洞地下暗河系统;（3）Ⅳ号岩溶地下水系统在平面和剖面上都没有与兰花隧道相交,不会对隧道突涌水构成威胁;（4）兰花洞地下暗河系统以中部兰花洞暗河天窗为界分为上游和下游两段,上游段Ⅰ号和Ⅱ号岩溶水系统在平面和剖面上都没有与兰花隧道相交,不会对兰花隧道突涌水构成威胁;下游段Ⅲ号岩溶水系统在平面上与兰花隧道相交（交点里程为DK60+100）,可能存在隧道突涌水风险;（5）依据高分辨率降雨-水文动态监测数据,采用降雨入渗系数法预测在极端暴雨情况下兰花隧道揭露Ⅲ号岩溶管道的最大涌水量为7.08×104 m3?d-1。      

岩溶地区地下水位变动带隧道涌水问题的思考

通过鸡冠山隧道涌水实例及广泛收集岩溶地区隧道涌水案例,总结出岩溶地区隧道季节变动带涌水具有反应时间快、水量大、泥沙重的特点,并综合分析地下水季节变动带隧道的水文地质特征,将其划分为一般山岭隧道及向斜构造地下水位变动带两种类型,且对两种类型涌水机理进行了阐述。岩溶地区隧道前期勘察应重点划分隧道岩溶地下水系统及地下水动力分带,查明岩溶发育特征与规律;施工期和运行期应结合岩溶揭露情况和涌水情况开展针对性的补充勘察,做好降雨、涌水过程和涌水压力监测,判断和预测最大外水压力和涌水量。针对涌水问题,提出封堵和排泄两种处理思路:施工开挖揭露的岩溶现象不可盲目封堵,需尽可能维持原通道的通畅,针对可能涌水的隧道衬砌设计不可仅考虑围岩结构,应充分考虑外水压力,做好围岩固结灌浆;常规隧道“环形排水系统+中心沟”排水系统可靠性差,针对大流量涌水,多采用泄水洞排水。      

Influence of rock mass properties on tunnel inflow using hydromechanical numerical study

One of the primary geotechnical problems encountered during tunnel construction involves the inflow of groundwater into the tunnel. Heavy inflows make tunnel construction difficult and result in higher costs and delays in construction period. Therefore, it is essential to estimate the volume and rate of water inflow that is likely to appear in the tunnel. In this research, water inflow to the tunnel was calculated using numerical hydromechanical analysis. Effect of rock mass properties including fracture characteristics (normal and shear stiffness, hydraulic aperture, dilation angle, and fracture nonlinear behavior) on inflow was studied using a two-dimensional distinct element method. Results show that fracture properties play important role in inflow to the tunnel and must be considered in prediction of inflow to the tunnel. Based on numerical analysis results, inflow of groundwater into the tunnel increases with the increasing of normal and shear stiffness, dilation angle, and hydraulic aperture of rock mass fractures. The measured inflow with considering nonlinear fracture behavior was more than the calculated inflow with linear constitutive behavior.     

某铁路隧道隧址区水文地质条件分析与洞身涌水量预算

通过详细分析隧道址区水文地质资料,认为石炭系灰岩、三叠系中统河湾组白云质灰岩和上统大水塘组下段安山玄武岩为强含水层组,大量的岩溶发育于石炭系灰岩和三叠系中统河湾组白云质灰岩中。以井水断层及太元背斜为界,将研究区分为太元背斜和街子坡复式向斜2个水文地质单元,并对各单元中水量、水质与地下水的补给、径流及排泄条件等进行了说明。采取并测试了13组地下水同位素样品,结果发现,区内地下水均来源于大气降水。应用地下水动力学和降水系数法对隧道洞身的涌水量进行了预测,推断隧道的正常涌水量为56 880m3/d,最大涌水量为68 300m3/d。为防止隧道塌方,提出了"短进尺、快循环、弱爆破、少扰动、紧封闭、超前注浆"的施工方法,并要求在施工中做好超前地质预测工作。     

Effect of Excavation-Induced Groundwater Level Drawdown on Tunnel Inflow in a Jointed Rock Mass

Analytical and empirical methods used in current engineering practice for estimating inflow rate into a tunnel do not adequately account for the effect of groundwater level drawdown which triggers changes of the flow pattern as well as reductions of the hydraulic head. When there is no reservoir or a large body of water near the tunnel alignment, the groundwater recharge above the tunnel might not be fast enough to avoid a significant excavation-induced water level drawdown. This paper provides analytical methods for estimating groundwater inflow rate taking into account the groundwater table drawdown. The proposed analytical solutions presented here compare well with field observations as well as with results from numerical analysis using distinct element method which can adequately simulate the hydro-mechanically coupled behavior of joints in a rock mass.     

The impact of groundwater discharge to the Hsueh-Shan tunnel on the water resources in northern Taiwan

The Hsueh-Shan tunnel is the fifth longest road tunnel in the world. During the excavation, the tunnel encountered several events of groundwater inrush, causing serious delay of the construction. Data on groundwater discharge to the tunnel were gathered from the monitoring system and their spatial and temporal variations were analyzed. The results of the integrated analysis of groundwater discharge and local precipitation indicated that the discharge increased rapidly when the cumulative rainfall exceeded 85?mm. The groundwater level recession rate after a rainfall event was found to be independent of rainfall intensity. A hydrogeological conceptual model was developed to simulate the long-term groundwater discharge to the tunnel. Sensitivity analysis was first conducted to identify sensitive parameters, and then the calibration process was accomplished by the automated parameter estimation method. The calibrated model was then used to evaluate the potential impact of tunnel excavation on the Feitsui reservoir; the average percentage loss of inflow to the Feitsui reservoir from 2006 to 2010 is estimated to be 1.74?%. The developed model can provide a tool for evaluating the regional hydrogeologic setting and the influence of tunnel construction on water resources.     

某隧道涌水量预测及地下水负效应环境评价

隧道的涌水量计算和对环境的影响一直是人们研究的重点。运用地下水径流模数法预测隧道涌水量,运用综合指标体系评价方法评价隧道对地下水环境的影响效应,为隧道对环境的影响提供依据。     

Prediction of water inflow to mechanized tunnels during tunnel-boring-machine advance using numerical simulation

An accurate estimate of the groundwater inflow to a tunnel is one of the most challenging but essential tasks in tunnel design and construction. Most of the numerical or analytical solutions that have been developed ignore tunnel seepage conditions, material properties and hydraulic-head changes along the tunnel route during the excavation process, leading to inaccurate prediction of inflow rates. A method is introduced that uses MODFLOW code of GMS software to predict inflow rate as the tunnel boring machine (TBM) gradually advances. In this method, the tunnel boundary condition is conceptualized and defined using Drain package, which is simulated by dividing the drilling process into a series of successive intervals based on the tunnel excavation rates. In addition, the drain elevations are specified as the respective tunnel elevations, and the conductance parameters are assigned to intervals, depending on the TBM type and the tunnel seepage condition. The Qomroud water conveyance tunnel, located in Lorestan province of Iran, is 36 km in length. Since the Qomroud tunnel involved groundwater inrush during excavating, it is considered as a good case study to evaluate the presented method. The groundwater inflow to this tunnel during the TBM advance is simulated using the proposed method and the predicted rates are compared with observed rates. The results show that the presented method can satisfactorily predict the inflow rates as the TBM advances.