RU2596617C1 - Method for drainage of ground waters on landslide slopes - Google Patents

Abstract

FIELD: ecology.

SUBSTANCE: invention relates to environmental safety and hydraulic construction and may be used for protection of the slope lands used in anthropogenic activities from landslide processes as well as additional source of replenishment of fresh water for household needs. Method involves formation of a drain trench on the bottom of side ditch of structural landslide, which is used for natural unloading of ground waters, with depth 2 to 30 m (depending on the level of groundwater occurrence) and width from 1 to 5 m (depending on depth of side ditch and density of primary rocks), which is led to a water accumulating reservoir for drain water with depth 2.5-3 and diameter 15 m formed on the first floodplain terrace. Tail-water channel with depth 0.5 m and width 1.5-2 m passes from the artificial water accumulating reservoir to the riverbed to control the volume of water and to create conditions for flowage in the reservoir. Method enables to use natural morphological parts of the structural landslide, in particular, the wedge-shaped lateral ditches (joints) of the landslide used for natural unloading of underground waters, thus reducing technological risks and ensuring environmental safety.

EFFECT: simultaneously provides reserve of pure fresh ground water for household needs of local population.

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Description

The invention relates to the field of environmental safety and hydraulic engineering and can be used to protect sloping lands used in economic activities from landslide processes, as well as an additional source of replenishment of fresh water for household needs.

There is a method in which a complex hydraulic structure of a drainage mine is formed from ventilation and water-reducing wells (patent for invention No. 2244063, published January 10, 2005).

However, the known method requires large investments and labor costs, has a narrow purpose and may cause additional problems associated with deep drilling and violation of the gravitational stability of the slopes.

There is also known a method of groundwater drainage, in which water is supplied from a water well to a water-absorbing well, which is located below the ground water slope (patent for invention No. 2338030, published November 10, 2008, IPC ЕВВ 3/18, ЕОВВ 11/00).

The known method is costly, since it involves the creation of two types of wells at a certain distance.

The closest technical solution is the method in which ditches, pits and wells, taps and pumping water are produced (patent for invention No. 2278208, published June 20, 2008, IPC EV 02/00).

The disadvantage of the prototype method is that it is not acceptable for sloping lands subject to dangerous landslide processes. In addition, complex work is underway to create water intake ditches, pits, wells in order to divert and pump water, which complicates the technical solution.

The technical result is a simplification of the method of drainage of groundwater and at the same time their use as an additional source of fresh water.

The technical solution of the claimed method lies in the fact that a drainage trench is formed at the bottom of the side moat of a structural landslide, through which there is a natural discharge of groundwater, with a depth of 2 to 30 m (depending on the level of occurrence of groundwater) and a width of 1 to 5 m ( depending on the depth of the lateral ditch and bedrock density), it is sent to and from the formed artificial reservoir reservoir of drainage water on the first floodplain terrace 2.5-3 m deep, 15 m in diameter for settling drainage landslide waters a channel with a depth of 0.5 m and a width of 1.5-2 m is led to the river bed to regulate the volume of water and create flow conditions in the reservoir.

The method is as follows. For drainage, the natural morphological parts of the structural landslide are used, in particular, wedge-shaped lateral moats (seams) of the landslide, these are longitudinal along the slope of the landslide body separation line, through which the natural discharge of underground groundwater causes the landslide movement. Often the lateral ditches fill up with soil over time, which complicates the further unloading of groundwater and leads to replenishment of the groundwater volume, which provokes subsequent shifts of the landslide body.

The parameters of the created drainage trench in the lateral ditch from 2 to 30 m are justified by the fact that the groundwater level on landslide slopes from place to place fluctuates mainly within these limits at the boundary of sedimentary and bedrock. Below 30 m, dense bedrocks occur, making trenching difficult. A side seam depth of less than 2 m is characteristic of deluvial surface landslides of low power, the movement factor of which is not groundwater, as in the case of structural landslides, but atmospheric precipitation.

The width of the created drainage trench at the bottom of the side moat is directly dependent on its laying depth: 1 m - for a depth of 2-10 m, 2 m - for a depth of 10-15 m, 3 m - for a depth of 15-20 m, 4 m - for a depth of 20-25 m, 5 m - for a depth of 25-30 m.

The created drainage trench is brought to the first floodplain terrace of the river, where an artificial reservoir with a depth of 2.5-3 m, a diameter of 15 m is created for settling drainage landslide waters, and a channel 0.5 m deep and 1.5-2 m wide is diverted from it riverbed to regulate the volume of water and create flow conditions in the reservoir.

Deeper than 2.5-3 m in the floodplain of the river groundwater. It is difficult to create a reservoir with a diameter of more than 15 m and a depth of more than 3 m in alluvial deposits, and it will not be filled with drainage water, because landslide groundwater is not a constant source. A pond with a diameter of less than 15 m and a depth of less than 2.5 m can quickly fill up with groundwater and rocky sediments and lose its purpose.

The created flowing reservoir contributes to the upholding of water and serves as a source of clean fresh underground water for the economic needs of the local population.

The formation of such drainage trenches in the lateral ditches of active large structural landslides of mountain slopes is proposed.

Example 1. In the side seams of a large structural landslide "Big Dallagkausky" drainage trenches are formed with a depth of 20-30 m, a width of 4-5 m. On the first floodplain terrace of the river. Mamisondon is created by an artificial body of water 2.5-3 m deep, 15 m in diameter, designed to filter and store landslide drainage water in order to replenish supplies of clean fresh groundwater for economic use, and a channel 0.5 m deep and 1.5 wide is diverted from it -2 m to the Mamisondon riverbed to regulate the volume of water and create flow conditions in the reservoir.

Example 2. In the side seams of the major structural landslide "Loire" formed drainage trenches with a depth of 10 to 20 m, a width of 3-4 m. On the first floodplain terrace of the river. Ardon creates an artificial reservoir with a depth of 2.5-3 m, a diameter of 15 m, designed to filter and store drainage landslide waters in order to replenish the supply of clean fresh groundwater for economic use, and a channel 0.5 m deep and 1.5 wide -2 m to the Ardon riverbed to regulate the volume of water and create flow conditions in the reservoir.

Example 3. In the side seams of large structural landslides "Zinsarsky" drainage trenches are formed with a depth of 2 to 10 m, a width of 2-3 m. On the first floodplain terrace of the river. Mamisondon is created by an artificial body of water 2.5-3 m deep, 15 m in diameter, designed to filter and store landslide drainage water in order to replenish supplies of clean fresh groundwater for economic use, and a channel 0.5 m deep and 1.5 wide is diverted from it -2 m to the Ardon riverbed, to regulate the volume of water and create flow conditions in the reservoir.

The formed drainage trench in the lateral ditches of the landslide mass separation contributes to the exit to the surface of the landslide groundwater and thereby reduce landslide activity. Drainage water from the trench enters and accumulates in the reservoir formed on the first floodplain terrace and serves as an additional source of clean fresh water for household needs. Water from the reservoir enters through the created channels into the river bed, regulating its volume and flow conditions.

Consequently, the proposed technical solution is characterized by a reduction in the cost of creating a drainage system (trench) for the removal of groundwater on landslide slopes, with their simultaneous use in the household needs of the population and the prevention of landslide disasters on sloping lands used in economic activities.

Claims (1)

A method of groundwater drainage on landslide slopes, including the formation of a drainage trench, characterized in that they form a trench at the bottom of the side moat of a structural landslide, through which there is a natural discharge of groundwater with a depth of 2-30 m and a width of 1-5 m, a drainage water reservoir on the first floodplain terrace with a depth of 2.5-3 m and a diameter of 15 m, a channel for draining drainage water from the reservoir to the river bed with a depth of 0.5 m and a width of 1.5-2 m.