Abstract: Based on turbulent flow and non-Darcy flow, the hydraulic conductivity calculating formula was derived by using hydraulic pressure in water injection borehole, length of the water injection part, hydraulic pressure and discharge in monitor borehole. With the test results of coal seam floor’s water-pressure in a mine, the difference of hydraulic conductivities under different flow status were analyzed, and it shows that the calculating result of hydraulic conductivity is greatly influenced by flow patterns, and the rock masses’ permeability can be changed greatly by hydraulic pressure. The paper provides an effective method for calculation of non-Darcy flow hydraulic conductivity in fracture rocks under turbulent flow conditions.

Key words: high water-pressure test, turbulent flow, non-Darcy flow, hydraulic conductivity