RU2399720C2 - Batter drainage of biopositive design - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: batter drainage of biopositive design comprises multi-layer filter made of flexible biopositive mats connected to each other. Mats are made of meshy shells and draining filler, which is arranged from layers of light fascines inside shells. Lower layers of fascines are laid normally towards direction of filtration flow, and upper layers - along with its direction. The mats themselves are in some areas pierced with metal wire. Flexible biopositive mats in areas of their connection on top are fixed with the help of reinforcement wire to concrete anchors arranged in lower slope above level of filtration flow and at the distance to each other. At the bottom near foot of lower slope flexible mats are on top loaded with heavier mats, meshy shells of which contain several layers of bags with local and vegetable soil below, and on top they contain tight layers of light fascines made of cane.

EFFECT: invention makes it possible to improve operational reliability of structure and helps to recover green zones near water edge in lower reaches of soil structures.

2 cl, 3 dwg

Description

The invention relates to hydraulic engineering and land reclamation construction and can be effectively used as a drainage device for low-pressure earthen dams and dams.

The closest technical solution is the overburden drainage, arranged on the lower slopes of earthen dams and dams, consisting of sand-gravel filters (return filters) and a stone sketch on top of them [1]. The main disadvantages of this technical solution are:

- the need for a large amount of stone and gravel material;

- high complexity of manufacturing inverse filters;

- low biopositivity and design efficiency.

The purpose of the invention is to reduce construction costs, increase the efficiency and biopositivity of the structure.

This goal is achieved by the fact that the layered drainage containing a multilayer filter is made of biopositive mattresses flexibly connected to each other, consisting of mesh shells and a draining aggregate, which is composed of layered rows of light fascia inside the shells, while the lower rows of fascia are laid normally to the direction filtration flow, and the upper rows are in its direction, and the mattresses themselves are sometimes stitched with metal wire. At the same time, the flexible mattresses on top are attached with reinforcing wire to concrete anchors arranged in the lower slope above the level of the filtration flow and at a distance from each other, and from the bottom at the bottom of the lower slope the flexible mattresses are loaded with heavier mattresses on top, in the net shells of which are bottom several rows of bags from local and plant soil are stacked, and on top are dense rows of light fascines from reeds.

In figure 1. shows a cross section of an earthen structure with overhead drainage on a lower slope; figure 2. - the same in plan; figure 3. - light fascin from reeds.

The bi-positive drainage drainage system consists of flexible mattresses 1 made of mesh shells 2 and a draining aggregate, which is composed of rows of light fascines. Moreover, the lower rows of fascia 3 are laid normally to the direction of the filtration stream 4, and the upper rows of fascia 5 are laid in its direction; in places, the mattresses 1 are sewn with metal wire 6. The flexible mattresses 1 are attached on top with reinforcing wire 7 to the anchors 8. The lower mattresses 1 are loaded with heavier mattresses 9 at the bottom of the bottom slope, in the net shells of which several rows of 10 bags of local and plant soil, and on top - dense rows of light fascin 11.

The overhead drainage of the biopositive structure is constructed as follows.

At the beginning, dry reeds are harvested in the required volume for the manufacture of light fascines 3, 5 and 11 in sufficient quantities, as well as bags from the geogrid, the dimensions of which can vary over a wide range (from 0.3 × 0.5 m to 0.7 × 1 5 m). They plan a downhill slope to the base, and at the base develop a trench for heavy mattresses 9. In the downhill slope above the level of the filtration flow 4, at the distance of the length of the mattresses 1, pits are developed between them and concrete anchors 8 are laid with reinforcing wires 7. After gaining sufficient strength with cast concrete in anchors 8, the size of the flexible mattresses 1 along the slope lay the mesh shells (gabion nets) 2 mattresses 1 with the attachment of pieces of metal wires 6. Then, in turn, make flexible mattresses 1, for this on the grid 2 over the entire area normal to the direction of the filtration stream 4 light fashions 3 are laid in dense rows, on top of which also the upper rows of light fashions 5 are laid in dense rows (perpendicular to the lower rows) in the direction of the filtration flow 4. Then the upper layer of the mesh shell is pulled 2 with attachment to the bottom layer of the net, the flexible mattress obtained in this case 1 is sewn with metal wire in some places 6. Then, exactly the same technology is used to make all the other mattresses 1 of the overflow drainage along l the bottom slope of the earthworks. All flexible mattresses 1 within the boundaries of their connection to each other are attached using reinforcing wire 7 to concrete anchors 8. Then, in the trench, located at the base of the bottom slope and on top of the lower part of the mattresses 1, the net shell of heavy mattresses 9 is stretched. stack several rows of bags 10 with local and vegetable soil, on top of which dense rows of light fascines 11 are laid. After that, the mesh shell around them is tightly pulled and the manufacture of heavy mattresses 9 is completed with simultaneous closure By warming to the retina 2 flexible mattresses 1. Bags 10 are pre-filled with local and plant soil (up to 30%) with the addition of seeds of hygrophilous and branched plants with a developed root system. Bags 10 can also be completely filled with vegetable fertile soil if it is in place in sufficient quantities. It is also recommended that in places on top of flexible mattresses in places to lay plant soil with sowing seeds of plants adapted to local conditions.

The drainage drainage of earthen dams and dams works as follows.

The filtration water flow under the influence of hydrostatic pressure in the upper pool (WB), moving through the body of the earthworks with a certain slope, goes to the lower slope, where the overflow drainage is located. In this case, filtered water is received by the lower rows of light fascia 3 located normally to the direction of the filtration stream 4. Next, the water passes into the upper rows of fascia 5 located along the direction line of the filtration flow, which quickly divert it to the downstream (NB). Due to the location of the lower rows of fashions 3 perpendicular to the direction of the filtration flow in tight rows, the possible contact erosion of soils at the base of the drainage is prevented. And the upper rows of fashions 5 work as drainage devices, due to their location in the direction of the flow of filtered water. Heavy gabion mattresses 9 at the base of the downhill slope and concrete anchors 8, arranged on top of the filtration stream 4, stably hold overflow drainage in the area of the outlet of the filtration stream and ensure the reliability of its operation. Over time, overflow drainage will overgrow with green plants, starting from the base of the lower slope, where heavy mattresses are located 9. The structure of light fascines from reeds contributes to the effective overgrowing of green spaces and an increase in the biopositivity of the drainage structure. At the same time, green plants do not significantly affect the filtration quality of drainage. With strong overgrowing with herbs and shrubs, the water supply ability of the upper rows of fascines 5 may decrease. And in this case, a safe drainage of the filtered water will be ensured, since part of the water will leak to the top of the drainage and go to the upper part of the drainage due to the large slope. For this, the required thickness of the water intake part of the drainage (lower layers of the fascia 3) and the drainage part (upper layers of the fascia 5) must be at least 20 cm of each part. It is advisable to make the thickness of the drainage part 10 cm thicker than the water intake part to ensure more efficient drainage of filtration water. The manufacture and installation of overhead drainage is carried out mainly by hand, partial use of technical means is possible when laying heavy bags in the base of the mattresses 9.

In the case of earthworks consisting of clay soils, small silty particles of soil may be transported by water particles to the water intake part, which will partially silt and become clogged with sediments (the lowest rows of fashions 3). In this case, filter back pressure (back pressure) may occur, which in turn can raise the flexible mattresses 1 of the drainage. Only a slight uplift can occur, which cannot lead to a serious violation of the drainage operation mode, since the reinforcing wires 7 and heavy mattresses 9 at the base will hold the flexible mattresses 1 in place. Partial lifting of the mattresses 1 will lead to washing of the lower silted layers of light fascin 3. After that, the normal drainage operation will be fully restored. The efficiency of the overflow drainage system will increase even further if a geogrid is placed in the clay base of the drainage, which will prevent siltation and clogging of the lower layers of fascines. 3. In the design of the drainage, the main filtration material uses dry reeds, which is a cheap local material that is widespread and has a large volume of flat sections of rivers (especially in the south of Russia).

Thus, the proposed overflow drainage design for low-pressure earthen dams and dams will provide for efficient reception and safe removal of filtered water through the body of structures at normal and forced water levels in the WB. At the same time, overhead drainage turns into a bipositive structure, which does not impede the circulation of substances and energy, helps the development of nature and is included in the river’s ecosystem, and is perceived by nature as a related element. Bi-positive drainage drainage can work effectively without major repairs for 10-15 years. Due to the fact that the bulrush is a highly draining and sufficiently resistant material, which is able to stay in the aquatic environment for 20-25 years or more. With periodic wetting and drying, the reeds retain their shape for 10-15 years and do not decompose. If the filtration properties of flexible mattresses 1 deteriorate over time, they can easily be replaced with new ones manually without the use of construction equipment.

It is recommended to use biopositive drainage in flat areas of rivers during the construction and reconstruction of low-pressure earthen dams and dams in areas where there are not enough stone and gravel material. And also - in hard-to-reach places where the use of heavy equipment is difficult.

The source of information

1. Waterworks. Designer reference. / Under the general editorship of Dr. tech. sciences, prof. V.P. Nedrigi.- M.: Stroyizdat, 1983, p. 171-173, p. 491.

Claims (2)

1. Drainage biopositive structure drainage containing a multilayer filter, characterized in that the filter consists of interconnected flexible biopositive mattresses made of mesh shells and a drainage aggregate, which is made up of layers of folded rows of light fascines inside the shells, while the lower rows of fascines are laid normal to the direction of the filtration flow, and the upper rows - in its direction, the mattresses themselves are sometimes sewn with metal wire. 2. Drainage biopositive construction according to claim 1, characterized in that the flexible biopositive mattresses in the places of their connection from above are attached using reinforcing wire to concrete anchors arranged in the downhill slope above the level of the filtration flow and at a distance from each other, and below from the soles of the lower slope, flexible mattresses on top are laden with heavier mattresses, in the net shells of which several rows of bags from local and plant soil are stacked below and dense rows of light fascines from reeds.

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