Dependence of fracture geometry and spatial variation in pressure on hydraulic conductivity in rock fractures

Kishida, Kiyoshi*; Hosoda, Takashi*; Sawada, Atsushi ; Sato, Hisashi; Nakashima, Shinichiro*; Yasuhara, Hideaki*

Although it is generally known that a natural rock fracture indicates a complex aperture distribution, the fracture is an ideal representation of the parallel plate model. The cubic law is applied to evaluate the hydraulic properties of fractured rock. From several previous research works, it is known that the cubic law can be applied when the Reynolds number is less than 1.0 and that the advection term can basically be ignored in such fracture flows. In this research work, two-dimensional seepage flow analyses, using the authors' proposed 2D model which is considered with the advection term, are carried out for single fracture hydro-conductivity experiments under conditions which allow for the application of the cubic law. From the numerical results, the validity of the 2D model is discussed along with the local Reynolds number and the application of the cubic law.