| When the seepage in fractured rock is numerically simulated, efficient calculation model, exact parameter of the model and reasonable boundary condition are mainly cared. The three matters are researched, and primary research conclusions are obtained.The main contents are as follows:(1) The four concerned equivalent methods used to simulate fractured rock are summarized comprehensively, such as continuum equivalent, statistic equivalent, admixture equivalent and dynamic equivalent. The advantages and disadvantages of every method are analyzed. Based on the analysis, the adaptability and equivalent characteristic evaluation of these methods is clarified.(2) The finite element theory about seepage in fractured rock is introduced. The effect of local water head loss is considered in seepage calculation for network fracture, and water head loss in every cross fracture is analyzed; The method for calculating equivalent permeability tensor is introduced, the criterions for determining the tensor validity are presented.(3) The seepage in transfixion and non-transfixion fracture network is analyzed. Based on the analysis, the effect of fracture geometry parameter for fracture network equaling to continuum medium is valued. The effect of nonlinear seepage and local water head loss for seepage field is researched. For non-transfixion fracture network, the sensitivity of the average value and standard error of the aperture, size, density, orientation of fractures in different distribution is mainly analyzed.(4) Two methods for obtaining permeability parameter of fractured rock are introduced. To counter the disadvantage of present methods, the corrected method is introduced. Based on numerical simulation of two-dimension packer permeability test, corrected formula of integration permeability coefficient is put forward. The method which can confirm reasonable and exact boundary conditions is put forward, and it is verified by an example.
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