RU1770519C - Dam drainage of earth materials - Google Patents

Abstract

Usage: in water construction, and more particularly in devices for lowering the depression curve and draining filtration water to the downstream of the dam from local building materials. SUMMARY OF THE INVENTION Two additional zigzag drainage lines and absorbent wells are connected to the drainage line; made in the form of filtering hemispheres from synthetic materials. 1 C.p. f-ls, 7 ill.

Description

The invention relates to waterworks construction, and more particularly, to devices for lowering the depression curve and draining filtration water into the downstream of the dam from local building materials, as well as increasing the stability of the lower slope, reducing steam and filtration pressures, preventing mechanical suffusion of soils at the base of the dam and prevent flooding of the area beyond the dam.

Known drainage of earth dams made of perforated concrete or asbestos-cement pipes laid with a slope parallel to the bottom of the bottom slope of the dam from soil materials. Every 50-200 m and along the length of the tubular drainage, wells are made of hollow reinforced concrete cylindrical elements (1). However, this device has drawbacks which are as follows: the water-holding capacity is low and the inability to exclude the deposition of a depression curve over the drain, which affects the reliability of its operation.

The aim of the invention is to increase the reliability of the drainage and reduce material consumption.

Figure 1 shows a section aa in figure 2; figure 2 - drainage of the dam, plan; in Fig.3 is a section bB in Fig.2; figure 4 is a section bb in figure 2; figure 5 is a cross section GG in figure 2; on figb - node I in figure 2; Fig.7 is the same, top view.

The drainage of the dam from soil materials consists of a main drainage line 1 having absorbent wells 2, to which, additionally zigzag drainage lines 3 with absorbent wells 4 are connected symmetrically relative to it. The drainage of the dam is laid on the pre-planned sole of the dam 5 in the dam body 6 and serves to intercept the filtration stream 7 and lower the depression curve in the body of the dam 6. The absorber wells 2 and 4 are hemispheres filtering from synthetic materials 9 and 10, limited watertight pallets 11, 12 below. Inside the absorber wells 2 and 4 there are stiffeners 13c

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with openings 14. The hemisphere 9 has openings 15 throughout its entire surface for receiving the filtration stream 7, for protection against siltation, the surface of the hemisphere 9 is covered with a fiberglass or silkworm filter 16, and a reinforcing mesh 17 is laid over the filter 16.

The work of the drainage of dams from soil materials is as follows.

After the dam is built and the reservoir is filled in the dam body after a certain period of time, the laminar flow of the filtration stream 7 is established. The filtration stream 7 is limited by the height of the dam 6 by the so-called depression curve 8. The task of drainage 1 is to intercept and discharge filtered water into the downstream and a decrease in the depression curve 8, respectively. A decrease in the depression curve 8 in the body of the dam 6 is necessary in order to prevent it from reaching a lower slope, because in this case there will be roiskhodit its destruction, as well as to prevent the approach of the depression curve 8 near the bottom of the slope near the surface than the depth of soil freezing, as in this case, the soil of the lower slope, frozen in winter, will thaw and heave in spring and summer, which will also lead to the destruction of the slope.

Lowering the curve of depression 8 and in the body of the dam 6 is also necessary in order to increase the overall stability of the bottom slope, as soil saturated with water is less stable, and therefore requires a greater slope, which in turn increases the volume of work and increases the cost of the construction.

In practice, the traditional measures to eliminate the above negative phenomena are to increase the downstream slope of the dam or to install one or several berms on it depending on the height of the dam, which, as noted above, leads to an increase in the volume of work and the cost of the structure.

Another negative phenomenon arising from the operation of dams made of soil materials is the flooding of the territory in the downstream. This is due to the fact that the filtration stream 7, min. Drainage 1 at the bottom of the dam 5, comes out and spreads over large distances in the downstream of the dam, thereby flooding valuable agricultural coal.

To combat this phenomenon, the drainage diameter for low-pressure dams (at a depth of 6–19 m in the upper pool) should be of the order of 1.5–3 m, which significantly increases the cost of construction and therefore does not go in practice. Another method, which is also very material intensive, is a combination

horizontal tubular drainage with vertical wells, or continuous drainage of territories in the downstream of the dam.

Exclude the above phenomena

allows the proposed device.

The filtration stream 7, passing through the body of the dam 6, enters the absorber wells 2 and 4 of the main 1 and two additional zigzag 3 drainage lines. Then it passes through the filter 15 of the hemispheres 9 and through the holes 15 it enters their inner space, and in the form of individual drops reaches the pallet 11. So

as the flow carries small particles of soil of the dam body, part of them settles in the filter layer 16 on the surface of the hemispheres 9, and others in the pallets 11, which are 30-40 cm deep below the drainage lines.

When the sump is filled, water is transported along drain lines 1 and 3 to the lower downstream, and from there to the water intake. The height of the arch of the hemisphere 9 allows you to adjust the position of the depression curve 8 in

the body of the dam 6. The angle a of the zigzag line controls the water-absorbing ability of the drainage over the area, which prevents the filtration stream 7 from leaving through the base 5 of the dam 6 and thereby

waterlogging in the downstream of dam 6 is excluded.

Claims (2)

1. Drainage of dams from soil materials, including a drainage line consisting of perforated pipes laid with a slope parallel to the bottom of the slope, and a drainage collector, so that and in order to increase Reliability and reduction of material consumption, the drainage is equipped with additional drainage lines located in the plan in a zigzag and symmetrical manner with respect to the main one, and well-absorbers. established in the places of excesses of additional drainage lines and their conjugations with the main one. 2. Drainage of dams according to claim 1, on the basis of the fact that the absorber well consists of a spherical arch made of synthetic filtering material and a waterproof pan with stiffeners inside. -h: t c 2uj 82 i r 0    .4 - .- .M Knot TL Ft. 6 IB FIG.