Experimental Study Of Water Flow And Solute Transport In A Single Fracture Of Roughness

The groundwater flow and solute transport in the fractured media is an important research aspect in hydrogeology of nowadays. The study on water flow and solute transport in a single fracture of roughness has important instructional significance on deep underground projects, prevention and cure of groundwater pollution and geologically treatment of radionuclide waste. This study is supported by Natural Science Foundation of China and Fok Ying Tung Education Foundation. Based on the study about water flow and solute transport in the fractured media at home and abroad, we study and analyze water flow and solute transport in the single rough fractures. A set of experiment equipment simulating groundwater flow and solute transport is designed. The test simulating groundwater flow and solute transport in the single rough fracture is performed. The validity of Darcy's Law and Fickian transport are incredulous in rough fractures. The water flow law in the condition of non-Darcy's flow state is analyses and concluded, and the phenomenon of non-Fickian transport is simply analyzed. The conclusions are drawn as followings: (1) The traditional Darcy's Law has difficulty in characterizing water flow in rough fractures and LCL (local cubic law) in the conditions of Darcy's flow state is invalid. The LCL is modified. Moreover, the study indicates that the values of n in the non-inosculated single fractures are accordant with more cubic law. (2) Dyeing tracer test indicates that the phenomena of turbulent flow are more evidence along with increasing of relative roughness degree in single fractures of roughness. (3) Based on experiment data, dispersion coefficient D_L is identified. The relationship between dispersion coefficient and velocity is studied quantificationally, and the results are compared and discussed with the former. (4) The breakthrough curves indicate that the phenomena of non-Fickian transport are evident.