【作者】 刘文剑；

【导师】 吴湘滨；

【作者基本信息】 中南大学 ， 国土资源信息工程， 2008， 博士

【摘要】 隧道涌水不仅威胁施工的安全、造成隧道结构的破坏,而且还对周边生态环境造成影响,因此,隧道涌水量预测不仅是水文地质学中一个重要的理论问题,也是隧道防排水设计和施工中一个亟待解决的现实问题。目前,隧道涌水量的预测方法很多,但是,其预测结果与实际情况往往出现较大的误差。针对这个问题,在总结前人研究成果的基础上,收集了雪峰山隧址区地质勘察和设计资料,并在施工期间进行了大量的地质调查、隧道围岩内部多点位移量测试验、涌水量测试分析,运用断裂损伤、裂隙介质有关理论,对雪峰山隧道的渗流场、应力场、涌水量预测及验证进行了较系统的研究:1)通过对雪峰山隧址区地质特征的研究,阐述了雪峰山隧址区地下水分布状况、岩体裂隙结构特征、裂隙介质的透水性以及渗透系数在空间上分布的层次性和随机性特征;2)归纳出裂隙介质四种印模破裂形态,运用最小二乘法迭代算法,推导出裂隙岩体地应力计算模型,并通过工程实例的实测数据加以验证及误差判断;结合数值分析的方法,分析了隧址区裂隙岩体地应力的空间分布特征;3)运用岩体蠕变和粘弹性断裂力学、可靠度等原理,对渗流场和损伤场在围岩位移中的变化规律和裂隙围岩可靠度进行探讨,建立了在裂隙岩体中隧道开挖的双场耦合蠕变模型和可靠度分析模型,结合Laplace变换,推导出围岩的径向位移函数表达式,论证了应力卸荷、渗流力作用,以及节理裂隙分布对径向位移和可靠度的影响;4)运用裂隙岩体的断裂损伤理论,结合渗流场与损伤场耦合关系和实测渗透系数、地应力数据,以及渗透系数的随机因素,分析渗透参数空间分布特征,建立了一种渗透参数与应力损伤耦合计算式;5)建立了隧道涌水量分析的工作程序和渗流场与损伤场耦合随机涌水量方程,即为裂隙岩体等效连续介质耦合渗流控制方程;结合渗透场与应力损伤场的随机特征,提出了在渗流与应力损伤耦合环境下,隧道涌水量预测计算的水文地质数值随机模拟法,并利用FLAC软件,建立了在渗流与应力损伤耦合环境下,隧道涌水量预测计算的水文地质数值随机模型的分析流程。6)考虑到地下水流经各层的面积、流量和渗透系数的关系,尝试建立一种层次渗透系数计算表达式,并结合工程实例进行预测及验证,论证了渗透系数空间分布对涌水量预测结果的影响;7)以雪峰山隧道ZK100+315～100+660段为例,采用传统的解析法、在耦合环境下平均渗透参数数值法与渗透参数空间差异分布数值法预测涌水量;并对预测结果与实测结果进行比较分析,探讨渗透系数、给水度(孔隙度)、水头高、降雨入渗量,影响半径等参数对涌水量的影响程度,并进行了随机变量的灵敏度分析。更多还原

【Abstract】 It is believed that the prediction of tunnel water gushing yield is not only one of important theory problem in hydrologeology but also one of urgent buring question, because serious influences is acted on builders’ security, tunnel’s structure and ambient entironment by water outflow. At present, there are a lot of prediction methods on tunnel discharge, but errors are appeared. Aiming at that problem, based on research results, data of geological reconnaissance and design, and measure experimentation of tunnel wall rock displacement, and testing analyses of water outflow, systematical researches of seepage field, stress field, prediction and validation of tunnel water inflow are done with fracture and damage mechanism, randomicity, fractured medium theory.(1) Based on geological characteristics investigation in XueFengShan Tunnel Section, groundwater distribution, structoural characteristics of cranny, hiberarchy and randomicity in fractured medium are analyzed, permeability of fractured rock and fractured medium are discussed.(2) Four types of moulage breakage form are sumed up. According to destruct features of fractured rock masses in the hydraulic fracturing process, mathematic model is induced for the account of geo-stress with the method of least-squares. Based on practical measure data of engineering noumenon, and errors are estimated. Combined with mathematic method, the dimensional distribution characters of geo-stress in tunnel section are analyzed.(3) Viscidity elastic fracture, creeping and random reliability theories are adopted, and double-field coupling creep model and reliability analytic model of tunnel excavation in rich fractured rock are established through researches of mutative rules and reliability of seepage field and damage field in fractured rock masses, laplace transformation is applied to educing the expression of radial deformation function, the influence of radial deformation and reliability are testified with geo-stress distribution, hydraulic pressure and joint distribution.(4) Applied rupture damnification theory , combined coupling connection of seepage field and damage field, and measuring data of hydraulic conductivity and geo-stress, and stochastic factors, spatial distribution characteristics are analyzed, new calculational expressions are educed.(5) The coupling random discharge equation of seepage field and damage field is set up, which is equivalent continuum medium coupling seepage control equation. Combined random characters of double fields, hydrogeology numerical simulation method which is adopted for the prediction of tunnel water inflow in fractured wall rock is brought forward under double fields coupling condition, its analysis flow is established with FLAC software.(6) In view of the relations among apiece layer area passed by groundwater, discharge flow rate, and hydraulic conductivity, hiberarchy hydraulic conductivity expression is founded, and is used to forecasting and validating with engineering noumenon. However, it is shown that space distribution of hydraulic conductivity impacts the result of water inflow.(7) Taking ZK100+315～100+660 section in XueFengShan Tunnel as an example, water inflow are predicted with three kinds of methods: analytic method,numerical value method considering coupling average seepage parameters, random numerical method considering space difference distribution of coupling average- seepage parameters. Their results illuminate that random numerical value method is reliable. Important parameters of discharge prediction relative to discharge infection: hydraulic conductivity, specific yield, hydraulic head level, accretion quantity of rainfall, radius of influence, are analyzed, Moreover, random variables sensitivities are analyzed. Based on the data of coupling average seepage parameters, water head level, and measured discharge, adopted numerical method, influence radius of infinite recharge partially penetrating type in phreatic aquifer is studied out.更多还原