RU2531852C2 - Method to test stability of snow cover on avalanche-prone slopes - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention relates to the field of testing of snow cover stability on avalanche-prone slopes of ski complexes with the purpose to ensure safety of recreation events performance. Substance: a dynamic force impact at a snow bed is effected, while the snow bed is adjacent to a near-comb zone of the ridge with the help of snow balls made and dropped off the ridge to the slope. In case of the dynamic force impact at the snow bed, it is first cut along the line of its most probable break from the upper and more stable part, then they additionally perform dynamic pointed impact at the snow bed with the help of snow balls, at the same time, if there was no avalanching during double testing, then the snow cover at the slope is considered to be stable.

EFFECT: increased accuracy of testing of stability of a snow cover at avalanche-prone slopes and provision of safety of recreation events at the avalanche-prone slopes of ski complexes.

4 cl, 2 dwg

Description

The invention relates to the field of testing the stability of snow cover on avalanche slopes of ski resorts in order to ensure the safety of recreational activities.

During various recreational activities on the slopes of ski resorts, the greatest danger for skiers is avalanches, which can break off the slopes during snowfall, after snowfall, in fog and clear weather. Avalanches are affected by a host of factors, such as the steepness of the slope, snowfall, temperature, wind, and also random mechanical influences. In this regard, ensuring safety through competent and timely testing of the stability of the snow cover on the avalanche-hazardous slopes of ski resorts is relevant.

There are various methods for testing the stability of snow cover on avalanche-hazardous slopes using specially designed stability scales that provide for the likelihood of avalanche formation by initiating impact on the snow mass (Guidance document "RD 52.37.752-2011. Organization and conduct of avalanche work on the territory of the Rosa Khutor Alpine Resort". - Nalchik, LLC Polygraphservice and T, 2011, pp. 9-10).

There is also a similar European scale for assessing the stability of snow cover (Website: zareferat5.ru/files-view-10512.html).

The stability scale provides for several gradations, which, unfortunately, are conditional and do not specify the essence of the method for determining the stability of snow cover on avalanche hazardous slopes.

There is also a method of testing the stability of snow cover on a slope before the start of the descent of skiers by dissecting the snow cover adjacent to the ridge area of the ridge, followed by a skier (Website: http://fizsport.ru/osnovy-metodiki-trenirovki/provedenie-trenirovochnykh-zanyatii-v -gorakh.

According to this method, the skier preliminarily runs a cross-country ski track near the ridge part of the ridge, thus separating (cutting off) the underlying snow layer from its upper part. If the snow layer is in an unstable state, then this operation can initiate an avalanche. However, this method is extremely dangerous and the organization on this basis of recreational activities on the slopes of ski resorts can lead to serious tragic consequences.

The closest in technical essence to the claimed object is a method for testing the stability of snow cover on avalanche slopes by dynamically applying force to a snow layer adjacent to the ridge zone of the ridge using snow "cores" made and dropped from the ridge onto the slope (FIPS Patent Decision RF for the invention according to the application No. 20111131103/28 dated 2012.10.26 (PROTOTYPE).

At the same time, this test method is not effective enough, since the dynamic force on the snow layer is point-wise, which does not guarantee reliable determination of the state and stability of the snow cover in the avalanche center. To ensure a full guarantee, it is necessary to know the minimum distance between point impacts, at which the dynamic impact on the snow layer could occur approximately along the line, and not pointwise. However, to determine the exact distance between the points of dynamic impact on the snow layer in real conditions is quite difficult.

The technical result of using the claimed method is to increase the accuracy of testing the stability of the snow cover on avalanche slopes and to ensure the safety of recreational activities on avalanche slopes of ski resorts.

The technical result is achieved by the fact that in the known method of testing the stability of the snow cover on avalanche slopes by dynamically applying force to the snow layer adjacent to the ridge zone of the ridge using snow "cores" made and dropped from the ridge onto the slope, according to the invention, when performing dynamic force impacts on the snow layer, they are preliminarily trimmed along the line of its most probable separation from the upper more stable part, then additionally They have a dynamic point impact on the snow layer with the help of snow "cores"; moreover, if avalanches did not occur during double testing, then the snow cover on the slope is considered stable.

The technical result is achieved by the fact that the cutting of the snow layer in the ridge region is carried out with the help of a load that is pulled along the snow layer with the help of a traction cable across the avalanche formation zone, forming a dividing groove on the snow layer along the line of its most probable separation from the upper , more stable parts of it.

The technical result is also achieved by the fact that a lead ball is used as cargo, or a pear-shaped cargo weighing 10-15 kg, which is fastened on one side with a climbing carabiner and cable suspension to a support rope stretched between opposite sides of the avalanche site, and the other side is attached to the traction cable.

The technical result is achieved by the fact that the cargo is pulled through the avalanche nucleation zone using winches, or manually, for which permanent anchors are fixed on the opposite sides of the avalanche site to insure operators and secure the winches.

Figure 1 presents the scheme of trimming the snow layer on an avalanche slope. Figure 2 shows the attachment unit of the cargo to the support rope using the suspension.

The method is implemented in practice as follows.

In accordance with the figure shown in Fig. 1, permanent anchors 1 are fixed on opposite sides of the avalanche center to insure the operators 2 and secure the winches 3. Then, the carrier rope 4 is pulled through the avalanche nucleation zone, which is attached to the anchors 1. To the carrier rope 4, stretched between the opposite sides of the avalanche site, with the help of a climbing carabiner 5 and a cable suspension 6 fasten the load 7, which may be in the form of a ball or pear-shaped. This site on an enlarged scale is shown in the figure (Figure 2). In this case, a lead ball weighing about 10-15 kg is used as cargo. A traction cable 8 is attached to the climbing carabiner 5, with which, using winches 3, you can manually move the load 7 along the support cable 4. Additionally, additional anchors 1 are placed along the ridge located between the opposite sides of the avalanche site to insure the operators 2 when moving along its edge. The length of the support rope 4 and the traction cable 8 is chosen so that the movement of the cargo 7 along the snow layer along a given route is ensured. To increase the reliability of testing, in some cases, you can use one more rope 9, one end of which is attached to a climbing carabiner 5, and the other end is on top of the ridge in the hands of operator 2, or attached to an intermediate anchor at the top of the ridge.

When testing the snow cover for stability, the snow layer is trimmed first. For this, the load 7 is either manually or by means of winches 3 dragged along the snow formation across the avalanche formation zone, forming a dividing groove on the snow formation, passing along the line of its most likely separation from the upper, more stable part of it. Moreover, in some cases, when there is significant accumulation of snow on the slope, the operator, moving along the ridge, pulls the rope 9 up and down, thereby providing a deeper run of the dividing groove, passing along the line of its most likely separation from the upper, more stable part .

Testing can also be carried out by one person, without the participation of technology. In this case, one end of the rope 9 is attached to the climbing carabiner 5 near the load, and the second end is on the top of the ridge in the hands of operator 2. The operator, moving along the ridge from one edge to the other, cuts the snow layer across the slope. In this case, the sum of the forces holding the snow layer on the slope decreases by

Fp = σ · h · L,

Where

σ is the tensile strength of snow, N / m ² ;

h is the thickness of the cut formation, m;

L is the length of the cut line, m

If the avalanche did not descend after pruning, then in order to finally verify the stability state of the snow cover, it is necessary to additionally force (point) the impact on the snow layer using snow "cores". To do this, previously prepared snow "cores" of a spherical or cylindrical shape, weighing 10-15 or more kilograms, are dropped or rolled off the slope, and if several hits of such "cores" on the surface of the snow cover on the slope do not provoke an avalanche, then that the snow on the slope is stable. After testing is complete, the slope is essentially ready for recreational activities.

After trimming the snow layer, the bearing rope 4 and the traction cable 8 are removed, and the load 7 is fastened to the safety anchor 1, located on board the avalanche site, using a cable suspension 6, and left until the next trimming operation.

Thus, the proposed method allows you to test the snow cover by two methods at once, which increases the accuracy of testing and thereby ensures the safety of recreational activities on the avalanche-hazardous slopes of ski resorts.

Claims (4)

1. A method of testing the stability of the snow cover on avalanche slopes by dynamically applying force to the snow layer adjacent to the ridge zone of the ridge using snow "cores" made and dropped from the ridge onto the slope, characterized in that when performing dynamic force on the snow layer they are preliminarily trimmed along the line of its most probable separation from the upper, more stable part, then they additionally carry out dynamic point impact on snow the first layer with the help of snow "cores", while if avalanches did not occur during double testing, then the snow cover on the slope is considered stable. 2. A method for testing the stability of snow cover on avalanche-hazardous slopes according to claim 1, characterized in that the trimming of the snow layer in the ridge zone is carried out with the help of a load that is pulled along the snow layer across the avalanche nucleation zone using a traction cable, forming on the snow layer dividing furrow, passing along the line of its most probable separation from the upper, more stable part of it. 3. A method for testing the stability of snow cover on avalanche slopes according to claim 2, characterized in that the load is a lead ball or a pear-shaped load weighing 10-15 kg, which is attached on one side with a climbing carabiner and cable suspension to the carrier a rope stretched between the opposite sides of the avalanche site, and on the other hand is attached to the traction cable. 4. A method for testing the stability of snow cover on avalanche-hazardous slopes according to claim 2, characterized in that the cargo is pulled through the avalanche nucleation zone using winches or manually, for which permanent anchors are fixed on opposite sides of the avalanche site for insurance of operators and fastening of winches.

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