SU1262293A1 - Device for measuring ground water level - Google Patents

Abstract

The invention can be used when measuring on reclaimed land under conditions of operational level change. To increase the speed and reliability of measurements under unsteady groundwater flow conditions, a perforated casing 2 installed in a well is filled with solid material 3 in cross section, the upper section of which is located from the bottom mark by the amount of capillary rise of water in it. An increase in the groundwater level causes a change in the shape of the meniscus formed during the rise of water in the capillary channels at the moment when the groundwater level reaches the lower controlled elevation. Periodic recording by the reflectometer gauge 6 of the roughness of the change in the reflectivity of the material 3 due to a change (A meniscus shape provides information about groundwater level fluctuations. The meter output signal corresponding to the upper limit level opens the groundwater level control equipment. 2 ill.

Description

The invention relates to techniques for measuring the level of groundwater, mainly to measuring the level of groundwater on reclaimed land under conditions of operational change "levels.

The purpose of the invention is to increase the speed and reliability of measurements.

Figure 1 shows a diagram of a device 1; figure 2 is a change in the shape of the meniscus with a change in water level.

Figure 1 shows a well 1, a casing 2, solid porous material 3 forming capillary channels 1, a perforated wall 4 of a casing, a perforated bottom 5 of a casing, a reflectometer for measuring surface roughness 6. 2

Figure 2 shows the meniscus shape at a water level below the upper cutoff of the solid porous material 3 (a), at the same water level with a cutoff mark of the porous material (S) and 2 at a water level above the mark of the upper cutoff of the porous material 3 (B).

The bottom of the casing is placed at the level of the lower limit mark of groundwater. The upper section of the porous solid material 3 is placed from the bottom mark by the amount of capillary rise of water in the material 3.

The device operates as follows. ·

From the moment the groundwater level reaches the lower controlled level, the water level rises in the capillary channels, forming a concave meniscus. The surface condition of the cut surface of the porous solid material 3 is recorded by a reflectometry roughness meter, the output signal of which is taken as the O reference. As the groundwater level rises, the shape of the meniscus changes - from concave to flat and convex. Periodically record the change in the reflectivity of the cut surface of the material 3 by a reflectometric roughness meter. Upon reaching the output signal corresponding to the upper limit level (determined during calibration), a command is issued to open ballast control equipment for regulating the groundwater level.

The effect of using the proposed device is to exclude flooded casing cavities, which ensures compliance with changes in the level of groundwater and at the same time changes in the state of the controlled cut (surface) of the solid porous material.

Claims (1)

Claim A device for measuring the level of groundwater, containing a perforated casing pipe installed in the well, and an optical measuring device installed above the wellhead, because of the fact that, in order to increase the speed and reliability of measurements in conditions unsteady groundwater flow regime, the casing along the cross section is filled with solid material forming capillary channels, and the measuring device is reflectometric and is located above the upper boundary of the material filling the casing th tube. ¢ 7 6 of FIG. 2 VNIIIPI Order 5412 / 37__ Circulation 705 Subscription Custom polygr. ave, city of Uzhgorod, unitary enterprise Project, 4