RU2560952C1 - Method for reducing underflooding of flood plains by flood waters - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: vertical or inclined absorbing wells are built on the side of one or both banks during the period of time, which precedes the flood season. Inlet sections of wells are closed by waterproof covers. By the time flood water flows, the covers are removed. Flood water is discharged to wells under action of force of gravity, wherefrom it enters stream underflows or accumulated in underground soil layers.

EFFECT: reduction of underflooding of flood plains.

2 dwg

Description

The invention relates to the field of river hydraulics, and in particular to a method of reducing flooding of river floodplains during a flood.

There is a method of protection against flooding of river floodplains by accumulating part of the river flow during the passage of large river flows in specially created artificial pools (reservoirs, ponds) and dumping the accumulated volumes of water during the low water period or using them for the needs of the national economy (Hydrology and hydraulic structures / G .N. Smirnov, E.V. Kurlovich (and others); under the editorship of G.N. Smirnov. - M .: Higher school, 1988. - 472 p .; Hydrotechnical structures: reference book of the designer / ed. V.P. Nedrigi. - M., 1983 .-- 544 p.).

The disadvantages of this method, with all its effectiveness, are the huge capital intensity, long construction periods, the need to withdraw large territories from the national economic turnover, significant changes in climatic factors, and the emergence of difficult to solve environmental problems.

A known method of discharging water into an aquiferous soil using a water-absorbing (absorbing) well ([Agroskin II Hydraulics / II Agroskin, GT Dmitriev, FI Pikalov. - M.-L .: Energy , 1964. - 352 p. S. 307]; [Chugaev RR Hydraulics (technical fluid mechanics) / RR Chugaev. - L.: Energy, 1971. - 552 p. S. 457]; [Shterenlikht D.V. Hydraulics / D.V. Shterenlikht. - M .: Energoatomizdat, 1984. - 640 p. S. 551]).

The disadvantage of this method is that it was used to discharge water by forced injection, for example, by pumps, and the dynamic level in the well was located below the surface of the earth.

The technical problem to which this invention is directed is to reduce the levels of flooding of the floodplain of rivers by flood waters without the use of pumps.

This problem is solved by the fact that in the method of reducing flooding of river floodplains by flood waters in the period preceding the flood, at lower points of the relief of the river floodplain, in the presence of a sub-river flow or in those sections in which the geological structure of the soil can accumulate significant volumes of water, at in the absence of underground engineering structures, absorbent vertical or deviated wells are built from one or both banks, the inlet sections of which are then covered with waterproof covers. According to the invention, by the time of the approach of the flood wave, the covers are removed, and flood water under the influence of gravity is dumped down, accumulating it in the underground layers of the soil or directing it into the underflow streams, thereby reducing the level of floodplain flooding or almost completely preventing floodplain flooding.

After the passage of the flood wave, the covers are returned to their original position at which the inlet section of the well will be closed. The frequency of location on the floodplain of water-absorbing wells is determined by hydraulic calculation.

Absorbent wells designed to receive flood waters are structurally designed so that, on the one hand, they ensure the integrity and operability of the structure over the entire proposed range of floodplain flooding levels and, at the same time, protect soil masses from the penetration of large surface erosion products (boulders, large stones, fragments of vegetation, wood chips, etc.). To do this, the inlet section of the well is covered with a trash-holding grate, and around this section after preliminary planning of the day surface a blind area is made of some hard-to-wash material (concrete, reinforced concrete, asphalt, etc.) for preparation with a slight slope (0.0005-0.005 ) to the well. The width of the blind area is calculated by the permissible speeds for the selected blind area material. The upper part of the well is reinforced with casing pipes (rings). Watertight covers of the wells are attached to the soil mass using anchors and flexible connections (chains or in some other way).

The advantages of the proposed method for reducing flooding of floodplains by flood waters are that it does not require the withdrawal of large territories from the national economic turnover, can be completed in a shorter time than the construction of reservoirs, and does not lead to significant changes in climatic factors or the emergence of difficult to solve environmental problems, It does not require the use of pumping equipment and, in general, is less expensive compared to other traditional methods of regulating river channels.

The essence of the method is illustrated by drawings, where in FIG. 1 shows a vertical section through a perfect absorbent well (s); FIG. 2 is a vertical section through an imperfect absorbent well.

A method of reducing flooding of a floodplain by flood waters is as follows.

In the period preceding the flood, at lower points of the relief of the river floodplain, in the presence of a channel bed or in those sections where the geological structure of the soil can provide the accumulation of significant volumes of water, in the absence of underground engineering structures, absorbing vertical structures are built from one or both banks or deviated wells 1 (Fig. 1), the upper part of which is reinforced with casing 2 or casing rings (not shown). The inlet section 3 of the well 1 is closed with a trash guard 4 and a waterproof cover 5 with a mounting loop 6, which is attached to the anchor 8 through a flexible connection 7. The approach to the inlet section of the well 1 is made in the form of a blind area 9 along the preparation layer 10 with preliminary planning of the daily surface of the earth with deviation of 0.0005-0.005 to the well. To prevent damage to the aquifer of the soil 11, the lower section 12 of the casing (casing rings) 2 is lowered below the natural level of groundwater 13 by h≈0.3-0.5 m, a mesh filter 14 is installed in the end part of the well to prevent hydromechanical suffusion of the soil and to protect the underlying layer 15 arrange backfill of gravel, gravel and large stone 16, made according to the inverse filter scheme.

When approaching the site in which the absorbent well was built, the flood wave 5 is removed using the mounting loop 6 from the inlet section 3 and the flood water under gravity, without forced injection, without the use of pumping equipment is dumped down, accumulating it in the underground layers soil 11 or directing into the under-stream flows, due to which they reduce the level of flooding of the floodplain or almost completely prevent flooding of the floodplain.

After passing the flood wave and exposing the input section 3 of the well 1, the blind area 9 and the trash screen 4 are cleaned of debris accumulated during the flooding, the condition of the anchor 8, the flexible connection 7 and the waterproof cover 5 are checked, and using the mounting loop 6 the cover 5 is returned to the original the position at which the input section 3 overlaps.

Thus, the presence of well-constructed wells in advance, appropriate operation and maintenance, can significantly reduce the negative consequences of flooding of river floodplains during floods.

Information sources

1. Agroskin I.I. Hydraulics / I.I. Agroskin, G.T. Dmitriev, F.I. Pikalov. - M.-L.: Energy, 1964 .-- 352 p.

2. Chugaev R.R. Hydraulics (technical fluid mechanics) / R.R. Chugaev. - L .: Energy, 1971. - 552 p.

3. Shterenlikht D.V. Hydraulics / D.V. Sterenlicht. - M .: Energoatomizdat, 1984. - 640 p.

Claims (1)

A way to reduce flooding of river floodplains by flood waters, consisting in the fact that in the period preceding the flood, at lower points of the relief of the river floodplain, in the presence of a channel bed or in those sections where the geological structure of the soil can accumulate significant volumes of water, in the absence of underground engineering structures, on the side of one or both banks construct absorbing vertical or deviated wells, characterized in that the inlet sections of the wells are covered with waterproof covers, in Yemeni approach flood wave lid is removed, and the flood water by gravity dropping down, accumulating it in the underground soil layers or steered in underflow streams.

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