Abstract: A test system of double medium seepage characteristics which is composed of double medium test module, water cycle system control module and data collection module is developed. The test system solves the key issues of porous media and fissure medium simulation, boundary conditions simulation, the perfection of water sealing technique and water exchange information collection, etc., and it has the characteristics of that the fracture width can be adjusted, higher precision, higher automation and test data real-time automatic acquisition. The test system of double medium seepage characteristics is used to study the distribution of water pressure that based on the water exchange and the seepage field of double-medium model, as well as the hydraulic behavior of double medium model and percolation mechanism. Using the test system of double medium seepage characteristics carries on the double medium seepage characteristics test and making use of the methods of trend diagram intuitive analysis, range and variance analysis and F-inspection, we obtained that water exchange factor of pore and fracture double medium exert the effects on the water exchange of double medium model. The influence ability of water exchange factor of pore and fracture double medium which are in the order, from big to small, are fracture width, porous media permeability coefficient, pressure gradient and water temperature.

Key words: double medium, seepage, hydraulic characteristics, test system, water exchange