RU2780705C1 - Permafrost meter - Google Patents

Abstract

FIELD: metrological instruments.

SUBSTANCE: invention relates to metrological instruments and is intended for measuring the depth of freezing and thawing of soil. The essence of the invention consists in creating a device for measuring the depth of freezing and thawing of soil without removing a transparent flexible hose from the casing tube, without strong digging of snow in the measurement area, as well as the absence of the need to pull out any probes and the use of additional measuring instruments. The permafrost meter contains a casing tube with a closed bottom filled with water, in which a flexible hose is placed with a gap. In the casing tube, closed from above with a lid with a central bolt fixed from the bottom of the lid with a nut, in addition, an inspection window with a scale and a drainage hole are made in its upper part, and an elastic plug is installed under the inspection window. Moreover, the flexible hose is made transparent with the lower end closed, passed through the central hole in the elastic plug and tightly put on the threaded part of the central bolt. At the same time, the flexible hose is partially filled with a tinted non-freezing liquid.

EFFECT: proposed device makes it possible after slightly excavating snow, only to the level of the raised non-freezing liquid, to visually register this level on a scale without violating the thermal regime on the ground surface in the measuring zone of its freezing and thawing, which is convenient when working observing the quality of the research conducted.

1 cl, 1 dwg

Description

The invention relates to metrological instruments and is intended for measuring the depth of soil freezing.

Known permafrost [1], which has received the greatest distribution in practical work. It contains a casing pipe with a hermetic closed lower end and an open upper end, installed in a soil well, the freezing of which is fixed. Inside the casing, coaxially with it, a rubber hose filled with water with a hermetically closed lower end descends from above. By removing the hose from the casing at certain intervals and probing it, the interface between ice and water is established and its depth is measured. It is conditionally assumed that this boundary corresponds to the freezing depth of the soil surrounding the permafrost.

In the known permafrost gauge, the presence of an air layer inside the casing pipe disrupts heat transfer from the soil to the indicator hose. And periodic extraction of the hose from the casing violates the stability of the thermal regime inside it, which leads to an increase in the measurement error.

Known permafrost [2], containing a casing with a closed bottom, filled with water, which is placed in an elastic tube filled with non-freezing liquid, connected to the internal cavity of the bellows associated with the recording node. The known device is difficult to manufacture, refill and adjust. It has insufficient accuracy and reliability due to the presence of a large number of poorly tuned complex closed small units and mechanisms.

Closest to the proposed device in terms of technical performance and the achieved result is a permafrost gauge [3], containing a casing with a closed bottom, in which, with a gap filled with water, an elastic hose with antifreeze liquid and a rigid probe with a flat extension at the lower end is placed coaxially. The known device is also difficult to manufacture and requires, when measuring, digging it out in the snow using an additional measuring tool.

The purpose of the invention is to improve convenience in measuring the depths of freezing and thawing of soils, reducing labor intensity.

To achieve this goal, a permafrost meter is proposed, consisting of a casing with a closed bottom, in which, with a gap filled with water, a transparent flexible hose with a closed lower end is placed, filled with a tinted non-freezing liquid, for example, antifreeze. An observation window with a scale, a drainage hole are additionally made in the upper part of the casing tube, and an elastic plug is installed under the observation window. From above, the casing is closed with a lid with a central bolt fixed with a nut, on the threaded end of which a transparent flexible hose is fixed, passed through a hole in the center of the elastic plug.

In FIG. 1 shows a vertical section of the permafrost.

The permafrost meter (Fig. 1) consists of a casing tube 1 with water 2, into which a transparent flexible hose 3 is lowered with a hermetically sealed lower end and tinted antifreeze liquid 4. In the upper part of the casing tube 1 there is also a drainage hole 5, an elastic plug 6 and an inspection window 7 with a scale 8. From above, the casing 1 is closed with a lid 9 with a central bolt 10 and a nut 11, on the thread of which the transparent flexible hose 3 is tightly put on by the upper end. on the threaded part of the bolt, but at the same time provides additional drainage in the transparent flexible hose 3, which is necessary for the passage of air when the tinted antifreeze liquid 4 moves in it. And the elastic plug 6 additionally centers the transparent flexible hose 3 in the casing pipe 1 and prevents it from entering water debris and snow. The device works as follows.

One of the permafrost meters is calibrated first. To do this, it is completely collected and filled with liquids in the following sequence.

Initially, the elastic plug 6 is lifted (Fig. 1) and through the viewing window 7 in the casing 1, water 2 is poured under it until it starts to pour out of the drainage hole 5. Then the tinted antifreeze liquid 4 is poured into the transparent flexible hose 3 until until the level of this liquid is set at the zero mark on the scale 8 in the viewing window 7. After that, the upper end of the transparent flexible hose 3 is tightly put on the thread of the bolt 10 held in the cover 9 by the nut 11. And the elastic plug 6 is returned to its original position, closing the water 2 from debris and snow and partially blocking the drainage hole 5.

Then the permafrost meter is exposed to frost in a vertical position until it is completely frozen. Water 2 in the casing 1 completely freezes, compresses the flexible transparent hose 3 and squeezes the tinted anti-freeze liquid up along the scale 8 located in the viewing window 7. Knowing the length of the frozen casing 1 and the amount of movement of the squeezed out tinted anti-freeze liquid 4, along the scale 8, we determine conversion factor, and conditionally accept it as constant for this type of casing pipes 1 and transparent flexible hoses 3 used in permafrost meters.

A pre-charged permafrost meter for operation is installed in the following sequence. Initially, a well of the required depth is drilled in the soil at the measurement site. Then the casing pipe 1 is lowered into it until the drainage hole 6 is aligned with the level of the soil surface. The gap between the casing pipe 1 and the edges of the well is filled with soil removed from the well.

When frost occurs, an ice crust is initially formed, both on the soil surface and on the water surface 2, which are at the same level due to the discharge of its excess through the drainage hole 5. Then, as the frost intensifies, the depth of freezing of the soil and water 2 in the casing pipe 1 increases Water 2, freezing, gradually squeezes the transparent flexible hose 3, raising the tinted antifreeze liquid 4 in it along the scale 8 in the viewing window 7 of the casing 1.

By visually measuring the movement of the tinted anti-freeze liquid 4 on a scale 8 and multiplying this value by the previously obtained conversion factor, the depth of soil freezing is determined without digging snow, pulling out a flexible hose and various probes.

Bibliography

1. Proceedings of the Scientific Research Institute of Hydrometeorological Instrumentation, vol. 1, 1950, No. 14.

2. Author's certificate No. 213384 USSR MPK G01K Device for recording the depth of freezing and thawing of soils / Danilin A.I., Komarov M.M.; applicant and patent holder All-Union Scientific Research Institute of Hydrogeology and Engineering Geology - No. 1096923 / 26-25 08/12/1966, publ. 03/12/1968, bul. No. 10.

3. Author's certificate 1144071 USSR MPK G01W 1/00 Frostmeter / Sokolov V.M., Sokolov A.S.; applicant and patent holder Leningrad Agricultural Institute and Leningrad Civil Engineering Institute - No. 3387472 / 24-10 Appl. 01/29/1982, publ. 03/07/1985, bul. No. 9.

Claims (1)

A permafrost meter containing a casing with a closed bottom filled with water, in which a flexible hose is placed with a gap, characterized in that in the casing, closed from above by a lid with a central bolt fixed at the bottom of the lid with a nut, an observation window with a scale is additionally made in its upper part and a drainage hole, and an elastic plug is installed under the viewing window, and the flexible hose is made transparent with a closed lower end, passed through the central hole in the elastic plug and tightly put on the threaded part of the central bolt, while the flexible hose is partially filled with tinted antifreeze liquid.

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