RU2368729C1 - Method for creation of drainage in foundation of tailings pond - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention is related to hydrotechnical construction of drainages in foundation of tailings ponds. Method includes arrangement of tubeless drains distributed along foundation area in the form of drain trenches deepened in soil with filtering filler and with surface protective layer in the form of reverse filter. Drain trenches are filled with elements of extended cylindrical shape, for instance wood lengths oriented in direction of drains axis. Central part of drain is made of cylindrical elements of larger diametre, and smaller diametre elements are laid along perimetre. Width of drain on top is assigned based on calculation of its water-receiving capacity provision by unloading of filtered drains from dump to drain perpendicular to its axis. Area of drain section is assigned based on calculation of its water-receiving capacity provision for diversion of collected drain flow in direction of drain axis.

EFFECT: invention makes it possible to increase reliability and corrosion resistance of drains in foundation of tailings ponds.

2 cl, 1 dwg

Description

The invention relates to the field of hydraulic engineering and can be used to create rock dumps and waste storage (tailing dumps), for example salt dumps of potash enterprises, on a drained base.

The design of tubeless drains is known, in which the main water-conducting element, then the core of the drain, is made of stone, gravel or brushwood and is blocked from the surface by a waterproofing material [1, p. 417, Fig. 19.3]. The disadvantage of such drains is the impossibility of their use for drainage of the base of dumps and waste storage, as:

- the design of the drainage does not provide for the intake of water (effluents) from above, from the body of the dump, the accumulator;

- the drainage capacity is insufficient to provide technological reverse water supply.

The closest technical solution is the drainage network at the base of the blade [2, p.21, Fig. 6; p.25, p.6.12], consisting of drains distributed over the base area with a tubular culvert and a surface protective layer in the form of a return filter. This solution provides the reception of effluents from the body of the dump and sufficient throughput to ensure technological reverse water supply.

The disadvantages of this solution are:

- restriction of the permissible depth of laying of tubular drains according to the condition of crushing strength of pipes (up to 17.5 m [1, p. 420, Table 19.7]), which does not allow their use for drainage of the base of large dumps and tailings, the height of which in some cases , for example salt dumps, exceeds 100 m;

- the inability to use pipes of the recommended assortment (concrete, ceramic, asbestos-cement [1, p. 420]) in an aggressive environment; for example, the liquid phase of saline waste is a saturated brine, which is highly aggressive to all of the listed materials.

The technical result of the invention is to increase the reliability of drainage of waste accumulators, to provide the necessary culvert capacity and corrosion resistance of drainages at the base of waste accumulators of any height.

This is achieved by the fact that in the method of creating drainage at the base of waste accumulators, including the device of distributed around the base area of tubeless drains in the form of drainage trenches buried in the ground with a filtering aggregate and with a surface protective layer in the form of a return filter, the drainage trenches are filled with elongated cylindrical elements, oriented in the direction of the axis of the drains, the central part of the drains being made of cylindrical elements of a larger diameter, and smaller elements are laid along the perimeter diameter, while the width of the drainage at the top is assigned in order to ensure its water intake for unloading the filtering effluents from the dump into the drain, perpendicular to its axis, and the cross-sectional area of the drain is designated based on the provision of its throughput for draining the collected drainage flow in the direction of the axis of the drainage. As elements of an elongated cylindrical shape for the culvert part of the drains, wood whips are used.

The structural diagram of the drainage is shown in the drawing, where the numbers indicate: 1 - dump waste, waste; 2 - base; 3 - preparation on the sides and bottom of the drainage trench; 4 - a protective layer of the drain in the form of a reverse filter; 5 - culvert element (core) of the drain from the elements of elongated cylindrical shape.

Drainage is created as follows.

For placement of dump rocks 1 of the future dump, a base 2 is prepared on which drainage trenches distributed over the area are arranged with deepening into the soil of the base. Drainage trenches pass with a slope according to the relief of the site for the development of dumping.

The width of the drainage trenches at the top is assigned based on the provision of the drainage capacity of the drain, and the cross-sectional area of the drain is designated based on the provision of its water throughput to divert the collected drainage flow in the direction of the axis of the drain.

The core of the drainage 5 is formed from elongated cylindrical elements, for example, wood whips, straight trunks without branches, branches, knots and peaks obtained from the forest logs at the dump site and laid in a trench in the direction of the drainage axis. Between the core of the drain 5 and the soil base 2 they prepare 3 (the bottom and sides of the drainage trench) by known methods to prevent the soil from being forced through the core of the drain.

It is known that wood in a salt solution without air access over time is gaining strength ("stony") and is not subject to decomposition.

Between the whips laid in the trench, channel-shaped voids are formed, providing a high drainage capacity.

When forming a drain, the central part of its cross section is made of large whips of wood, and whips of smaller diameter are laid along the perimeter. A protective layer 4 is placed on top of the drains in the form of a return filter.

The use of tubeless drains with the formation of the core of drains by elongated cylindrical elements provides:

- increased throughput due to the presence of channel-shaped voids between the wood trunks oriented in the direction of the axis of the drain, and a large total cross-sectional area of these channels;

- increased crush strength due to the use of solid round trunks in contrast to a hollow pipe of annular cross section;

- high corrosion resistance of the drainage structure due to the work of wood under conditions of constant temperature and humidity conditions.

These advantages allow you to create waste storage (dumps, tailings) on a drained base without limiting their height and service life.

The drainage method is as follows.

On the prepared base 2 with finished drains 5 produce dumping (washing) of waste. The filtrate released from the dumped (washed) waste 1 seeps to the base 2 and is collected through the permeable protective layer 4 by drains buried in the base, and then through the channel-shaped voids between the whips of the trees that make up the core of the drain 5, it is discharged outside the dump.

The application of the proposed method for creating drainage at the base of waste accumulators of any height ensures their reliable drainage, the necessary throughput, corrosion resistance and durability.

Information sources

1. Foundations, foundations and underground structures. Designer reference, ed. E.A. Sorochana. M .: Stroyizdat, 1985 (p. 417, Fig. 19.3); (p. 420, table 19.7).

2. P 64-77. Guidance on the design of drained ash dumps of thermal power plants. VNIIG them. B.E. Vedeneeva, L., 1977 (p. 21, fig. 6; p. 25, p. 6.12).

Claims (2)

1. A method of creating drainage at the base of waste accumulators, including the device distributed across the base area of the tubeless drains in the form of drainage trenches buried in the ground with filtering aggregate and with a surface protective layer in the form of a return filter, characterized in that the drainage trenches are filled with elongated cylindrical elements, oriented in the direction of the axis of the drains, the central part of the drains being made of cylindrical elements of a larger diameter, and elements of a smaller diameter are laid along the perimeter meters, while the top drainage width is assigned in order to ensure its water intake for unloading filtering effluents from the dump into the drain, perpendicular to its axis, and the drainage cross-sectional area is assigned based on ensuring its water throughput to divert the collected drainage flow in the direction of the drainage axis. 2. The method according to claim 1, characterized in that as the elements of an elongated cylindrical shape for the culvert part of the drains, use wood whips.

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