裂隙岩体渗流模拟的三维离散裂隙网络数值模型(Ⅰ):裂隙网络的随机生成

NUMERICAL MODEL OF THREE-DIMENSIONAL DISCRETE FRACTURE NETWORK FOR SEEPAGE IN FRACTURED ROCKS (Ⅰ):GENERATION OF FRACTURE NETWORK

对于裂隙岩体中的渗流来说,离散裂隙网络模型比等效连续体模型更能刻画其基本规律。发展了用于模拟裂隙岩体渗流的三维离散裂隙网络数值模型,并编制了裂隙岩体渗流模拟程序FracFlow。该模型可以利用野外露头上采集到的裂隙的观测数据,通过计算机处理最终形成三维裂隙网络的人工几何模型,然后用边界元法求解所生成的裂隙网络中的渗流问题。在此第一部分中,介绍了利用计算机随机生成三维裂隙网络的详细过程,然后利用算例校核了程序的正确性。

A numerical model of three-dimensional discrete fracture networks for seepage in fractured rocks is presented. Fractures are modeled as circular or quadrangular disks with arbitrary size,orientation,location and transmissivity. A fracture network is characterized by the statistical distributions of these parameters. Based on this model,a code for predicting seepage in fractured rocks,FracFlow,is developed,which can estimate the statistical distribution of the appropriate geometric parameters through field measurements,generate statistically identical fracture network,and compute the flow responses of this fracture network. The program can also use site-specific geometric data to generate fracture network. Boundary element method is used to discretize the fracture network and solve the problem of seepage. In the first part of this paper,only the detailed process of the generation of three-dimensional stochastic fracture networks using field data is introduced. At last two samples are given for the calibration of this program.