| 摘要 |
PURPOSE:To raise the reliability of a permeability test by a method in which compressed air is sent into an enclosed casing, ground water is pumped up, the casing is opened, the ground water is introduced into the casing. The variations in water level and time taken until the ground water becomes equilibrated are measured to obtain the coefficient of permeability. CONSTITUTION:When sending compressed air into an enclosed casing 2 through an air supply tube 5, the internal pressure of the casing is raised and ground water inside the casing is discharged through a water pumping tube 3 to the outside. When the completion of the discharge of the ground water from the casing 2 is detected by a water level detector 8, the enclosure of the casing 2 is released, whereby the internal pressure of the casing 2 is lowered and ground water 7 is introduced into the casing 2. The time taken until the ground water 7 becomes equilibrated and the variations in water level are measured by a water level detector 8 to obtain the coefficients of permeability at given depths of the ground. |
