| 摘要 |
PURPOSE:To survey the movement of ground water precisely by digging a boring hole of small bore diameter and measuring the three dimensional flow directional flow velocity of water in each water level in ground water in the hole. CONSTITUTION:Existence of permeated water 1 and existence of an impermeable layer 2 are ascertained by a survey of the ground surface and the surface level 5 of ground water is ascertained by an observation well 4. Boring holes 6a, 6b,-of small bore diameter are digged at the position required. A sensor is inserted into the hole to measure the three dimensional flow directional flow velocity of water in each water level of the ground water surface 5. The sensor consists of >=3 pieces ultrasonic wave oscillating elements 11, a ultrasonic receiving element 12 at the central part and a measuring part 13 incorporated with a direction detector. Measured data are transmitted to the ground by a communication cable incorporated in a flexible cable 14 and calculated by an analyzer to grasp the perfect movement of ground water at a measuring area from the result about the plural boring holes. |
