Determination Of Permeability Tensor By Three-dimensional Fracture Network Of Rotation Whole Model Method

It is very important to study the seepage characteristics of fractured rock,which is of great significance to oil and gas exploitation,soil and water development,environmental protection and gas storage.The hydrodynamic characteristics of fractured rock mass play a very important role in large rock mass engineering,such as dams,underground tunnels,nuclear power station foundation and oil storage.In this paper,the fractal network model is used to analyze the seepage of rock mass,and the spatial storage model of fracture is optimized by using adjacency matrix.In order to obtain the accurate three-dimensional permeability tensor,the computer fractured rock And the influence of the geometric parameters of the fractured rock mass on the permeability coefficient of the rock mass was investigated by controlling the variation of the single variable.The details as follows:In this paper,the intersection of adjacent disk arrays is used to store the intersection of the crack discs,and the effective fissures are stored directly according to the connected components.Compared with the use of two-dimensional arrays,the fractal dimension of the fissure discs is much larger than that of the two-Storing the intersection of slit discs saves a lot of memory space.Based on the simplified discrete fracture network model of pipe unit,two aspects of determining the permeability tensor are proposed for the analysis of seepage problem using the equivalent continuum model.The computer simulation of fractured rock mass with different sizes is carried out to calculate the corresponding hydraulic gradient direction and the degree of penetration is analyzed to determine the degree of stability of the permeability tensor.The rotation of the fractured rock mass network is rotated by rotating the three-dimensional object to fit the permeability coefficient in each direction and the degree of similarity with the ellipsoid is investigated.Tensor existence.The corresponding numerical model is simulated by the measured field parameters.Compared with the measured value,the main permeability coefficient and the main direction error are both about 20%.The parameters of the discrete fracture network are used to characterize the spatial distribution of fractured rock mass,which forms the basis of the fracture network model.Therefore,the geometrical parameters of different rock fissures have influence on the permeability of established fracture network model.The influence of different hydraulic parameters on seepage flow in fractured rock mass is analyzed,and the influence of trace length on permeability coefficient is found.Trace length increased 1 to 2 times,the permeability coefficient increased by about 9 times.