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For solving the problems of scientific practicel method, since human birth has never stopped Heterogeneity of fractured rock mass characteristics, can be random or a function can also be described, in what way, depends on the parameters of its average level of random fluctuation, or the parameters can be expressed as a function of the variations. Li Huaye pointed out, there was a fractured rock can not be used causal relationship to strictly controlled or accurately predicted the phenomenon, this phenomenon can only be for a comprehensive analysis, excludes certain factors, summarizes some of the law from which. Obviously, the discrete nature of fractured rock is expressed statistical functions available.In this paper, as the research object of Jinping Hydropower Station, according to the current problems in the study of the rockmass, in engineering science as a guide hydrogeology, useing of hydrogeology, rock mechanics, structure theory of geology, earth science, combining probability, statistics, and philosophy of mathematics and sociology, studies the fracture characteristics of stratified rock and the discrete model modeling methods in the construction, connectivity calculation; obtains the following main conclusions:1,The stratified rockmass in the study area can be divided into three typesBased on the understanding of the marble and slate rock on the sand or their combinations relation in the study area,Marbles can be divided into 8 small layer by color, structure and geological features, sandy slate can be divided into 4 small layer of stratified rock mass classification.According to the interbedded between,in accordance with Chen Zhijian’s theory on the stratified rockmass, with distribution of crack development and construction of an integrated analysis of Study area,12 small layer by divided into A, C, E three types. The fractures in rock mass performance of hidden cracks closed of A, and the level of superiority obvious, the main grounds are T2-3Z3(3), T2-3Z3(1); C class from the soft rock in the fractured rock restrictions, spacing much in the 50 cm, but a larger depth of cut, a longer extension,with the main ground for the T2-3Z2(3)～2(8); E Class closes mostly hidden cracks in rock fissures, level of advantage is not obvious, the main formation T2-3Z2(1)～2(2).2, Fractured characteristics of the study area(1)The dominant fracture groups:In the study area, the paper mainly develops V grade structural surface, based on the density of fractures in each group, combins with previous research results, thinks that the dominant fracture groups are five; the left bank have two groups:①100～175°∠40～75°(SL);②344～45°∠70～90°(Ⅲ-1);the right bank have three groups:③120～188°∠55～90°(Ⅳ);④265～350°∠20～60°(Ⅰ);⑤188～230°∠50～90°(Ⅲ-2).(2) Fracture spacing:In view of the characteristics of crack spacing data, the paper introducts the exploratory data analysis method, data distribution shows, data analysis and data analysis results, by boxes-chart;and provids the median instead of the mean, refers to the variance and the calculation,defines the variance parameters to describe the fluctuations of the median,gives the formula and the calcalation method of 95% confidence interval. Based on the new method, in the study area, the data of the dominant fracture sets shows a negative exponential distribution,spacing are less than 50cm, confirmation crack density rating of "Ⅳ-development" by the identification and description standards of its rocks and rock.(3)Fracture aperture:the dominant fracture of wide data gap fracture group, with the frequency histogram icon, are negative exponential distribution,with the statistical mean gap width of 0.33mm, according to ISRM classification standard fracture, can be described "partially open", and its status is "closed", the relative permeability "10-4～10-2cm/s".With the Perceptual field, talks about the data attributes and laboratory methods of the grey system.(4)Trace length:the mean trace length of the dominant fracture, with an infinite window, HH trace length are between 3～4m, according to ISRM proposed the grading standards of the surface continuity of the structure, is a continuous medium sex; with frequency histogram icon, SL andⅢ-1 trace length showed normal distribution, other groups are lognormal.3, The study area local discrete fracture network visualization and analysisUsing GeneralBlock software, reproducted the fracture three-dimensional network of the banks of in small-scale, and using the theought of "from a single to the combination", designs three dimensional fracture network,and does a detailed analysis of rock mass fracture law,distribution and its connectivity.(1)Left:two cracks form an effective connectivity only a limited range of local connectivity within the region,and very random. SL has more crack extension and the spacing thanⅢ-1, scattered distribution; the effective connectivity network is seen inⅢ-1 intensive development zone,SL conductivity effect.Type model through statistical profile of their representatives (Y-Z) and the plane (X-Y) fracture,calculats the number of intersections per square meter, is 0.01.(2)Right:The crack fracture network concludsed of three dominant groups has more connectivity, the fracture network characteristics ofⅣandⅢ-2 of the profile composition is significantly, and withⅠandⅣsymbiotic crack, amplies the features;Ⅳplays through upper-right to down-left,ⅠandⅢ-2 portfolie a "#" distribution in the meantime. From the role of fracture network,Ⅳfracture sets both the catchment corridor fracture network, but also guides the water channel; I is both a watershed corridor, but also storages space;III-2 compared to other groups,mainly froms the water effect. The intersection number per-square meter of the right bank, is 0.2, and its connectivity is far greater than the left bank.4,The fracture network control parameter sensitivity analysisAccording to GeneralBlock software, designs the fracture model generation program of the control fracture occurrence and the radius parameter fluctuations, discusses the distribution and connectivity trends.(1)Inputs the statistical results of the measured data directly (A program), the results chart shows a large single fracture random fluctuations remarkably, fissure between the two groups form a cross, and are inconsistent with the theory and field observations;(2)The occurrence parameters remains stable, the radius of the control parameters of trace length increases volatility (A-1 program), the fracture distribution significantly, and in accordance with theory and field observations; trace length fluctuations, does not affect the simulation of dense and sparse fracture zone area, but will increase the network connectivity;(3)The radius keeps stable and occurrence parameter fluctuations (A-2 program), not only change the distribution of cracks, the original dense areas become sparse areas, the original sparse area become a concentrated area, will also enhance the connectivity of simulation region performance, but a slight discrepancy with the field observations;(4)In concluded, that radius fluctuations only change a single fracture fluctuations,not only effect the simulation area, but also change a single fracture geometry is tantamount to increasing the number of the fracture group, the occurrence is the key factor to build the models. Different fracture should be used different control methods of the factor in the simulation, the construction of steep dip and unloading fissures,because the error is small and the trace length error, should control the occurrence, the radius appropriatly fluctuate; and smooth layer fracture should be the opposite.The major innovations:(1)the measured data of the fracture characteristic parameters, according to their different distribution types of data using different statistical methods;(2)based on data analysis, bulids a set of the discrete model simulation program to control parameters, explores the complex models and the sensitivity analysis method of its parameters.
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