SU75689A1 - Groundwater pressure gauge - Google Patents

Description

According to the invention, an apparatus is provided for measuring the pressure of groundwater, made in the form of an electrically operated membrane type dynamometer, intended for embedding into the soil, moreover, the nozzle dynamometer is applied to the soil dynamometer.

The device of the device proposed is illustrated in FIG. 1 and 2 of which the device is shown schematically in two projections.

The device made in this embodiment consists of a housing 1, a membrane 9, a cover 10 and an electromagnet 7 installed inside the housing / on a boss 5; On the membrane 9 there are brackets 3 carrying the string 2. Outside, the nozzle 4 is screwed onto the housing 1, which is a thick perforated iron plate with a hole. mi 6, not bend, usus under the action of the ground.

The holes 6 in the nozzle 4 and the cavity in contact with the membrane 9 are filled with a viscous liquid II, for example, grease, which prevents the soil particles from coming into contact with the membrane and transmitting it to it. Sun ka particle

having got into a viscous liquid, it begins to experience uniform pressure on all sides and therefore cannot move towards the membrane. The viscous fluid displaced by this soil particle will, in turn, displace water or air from the nearest soil pores, with the result that the balance of forces in the immediate vicinity of the plane of contact is not disturbed.

In the case of the presence of groundwater, the pressure is transmitted completely and without distortion to c. viscous fluid and through it to the membrane 9.

Some modification of the membrane 9 of the dynamometer described, as compared with other devices of this type (thickening of its middle part), is caused by the desire to minimize the membrane deflection so that the volume of fluid that is necessary for the operation of the device over the full range is minimal.

The proposed improvement makes it possible to measure the pressure of water in any microporous medium, and, due to the extremely small volume of water required to record the pressure, allows the instrument to react to a change in this pressure almost instantaneously.

439

The indicated advantage and complete impossibility of silting makes the proposed device convenient for studying hydrodynamic pressures in a wide porous medium, and especially in alluvial structures, a .-. B ;; Soils with small coefficients of filtration, popes in clays.

The subject of the invention $}

The instrument for measuring the pressure of groundwater, made in

FIG. one

FIG. 2

An electric membrane-type dynamometer, intended for embedding into the ground, is required so that, in order to prevent the dynamometer from affecting the pressure of the ground itself, a nozzle, made in, is attached to the Iamometer membrane. As a non-absorbent soil, the action of the soil is of a plate of considerable thickness, equipped with a number of narrow: concentric holes or slots filled with some kind of viscosity: liquid, “anpiM.ep, grease.”

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