| 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.
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