WANG Xinyong,WANG Xiyong,ZHANG Yangsong,et al.Study on Connected Path of Rock Fracture and Equivalent Permeability Tensor Parameters of Rock Mass[J].Journal of Disaster Prevention and Mitigation Engineering,2020,40(05):789-795.
WANG Xinyong,WANG Xiyong,ZHANG Yangsong,et al.Study on Connected Path of Rock Fracture and Equivalent Permeability Tensor Parameters of Rock Mass[J].Journal of Disaster Prevention and Mitigation Engineering,2020,40(05):789-795. DOI: 10.13409/j.cnki.jdpme.2020.05.014.
Study on Connected Path of Rock Fracture and Equivalent Permeability Tensor Parameters of Rock Mass
In the disposal of high-level nuclear waste, mastering the seepage law of groundwater in fractured rock mass is a key issue at present. With the engineering background of a surveying area in Gansu Beishan, the discrete fracture network model in the global domain was generated using the MATLAB code based on the statistical parameters of fracture properties measured by field data. The three-dimensional disc-shaped fractures are modeled and simplified as channel element network with variable cross-sections, and each channel element is cut in the research cube for the consideration of the edge effect. Then the Representative Element Volume (REV) is characterized by comparing the trend of the equivalent permeability coefficient in three directions which changes as the size of research cube is getting larger; the permeability tensor is calculated and the optimum path of the corresponding boundary direction is recognized by use of the improved Dijkstra algorithm in this REV cell. The results show that the maximum and minimum values of the permeability coefficient of the measured area are 3.62e-6 m/s and 9.19 e-7 m/s, respectively, which has the lowest permeability in horizontal plane and the highest one around the vertical direction, and this results are basically in line with the actual project. All these programming ideas and simulation results can provide a reference for solving related engineering problems.
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