RU2709040C1 - Method of monitoring the filtration state of a ground dam with a clay-cement-concrete diaphragm - Google Patents

Abstract

FIELD: hydraulic engineering.

SUBSTANCE: invention relates to hydraulic engineering and can be used as a method of monitoring the integrity of waterproof structures of hydraulic structures from soil materials. Method of monitoring the filtration state of a ground dam with a clay-cement-concrete diaphragm includes a device on the side of the lower part of the tubular drainage for collection of water filtered through a dam, and draining of the drainage drain into the common water intake collector. During erection of the ground dam the waterproof flange is arranged along the whole filtration front in the lower part of the reverse filter on the side of the lower part of the ground dam. Drain tube consisting of short sections with length of 1–1.5 m along the entire filtration front is laid at a distance from the axis of clay-cement-concrete diaphragm within range of 0.8–1.0 of its width. Drainage tube is connected to each local section of the drain tube and each drainage tube is brought out to the common viewing loss.

EFFECT: technical result consists in providing possibility determination of filtration state of ground dam with clay-cement-concrete diaphragm, determining locations of possible damage in clay-cement-concrete diaphragm with accuracy of 1–1,5 m, quantitative assessment of volume (flow rate) of water filtration through damages in clay-cement concrete-concrete diaphragm, reduction of terms and costs for their detection and elimination.

1 cl, 3 dwg

Description

The invention relates to the field of hydraulic engineering and can be used as a method of monitoring the integrity of the anti-filter elements of hydraulic structures from soil materials.

A known method of monitoring a clay-cement diaphragm in an earth dam (patent of the Russian Federation No. 2628447, published August 16, 2017), including laying a fiber-optic temperature sensor along the entire area of a cement-cement diaphragm from the downstream side and connecting it to a readout fiber-optic transceiver that determines the place of damage and the amount of leakage through the cement-cement diaphragm. During the construction of the soil dam, its height in the area of the subsequent creation of the cement-cement concrete diaphragm is used to pour waterproof shelves from loam with a step of 1.0-3.0 m and a slope i towards the downstream to direct the water flow towards the location of the fiber-optic sensor temperature laid along the edges of waterproof shelves.

The disadvantages of the analogue are the need to arrange a large number of shelves with a step of 1-3 m over the entire height of the diaphragm, which requires additional costs for the soil material of the shelves and quality control for performing these works, the large cable length of the fiber-optic sensor, laid continuously across all shelves, the impossibility of repair fiber-optic sensor during the operation of the soil dam, the use of additional equipment, such as a transceiver and the associated costs of its operation.

There is a traditional way to divert and control the amount of water filtered through the body, base and coastal junctions of the dam into the downstream (SP 39.13330.2012 Dams from soil materials. Updated version of SNiP 2.06.05-84 *, p. 5.52, 5.58). The essence of the method lies in the fact that they perform tubular drainage from the downstream side of the soil dam along its front, install drainage wells along the drainage, for example, after 100-200 m, then arrange a drainage collector in the form of a discharge ditch or channel and make water outlets from the observation wells in the drainage collector.

By the greatest number of similar features and the achieved result, this technical solution is selected as a prototype.

The disadvantage of the prototype is the inability to control local sections of the filtration flow along the length of the dam (drainage costs), taking into account the layout of the inspection drainage wells with a step of 100-200 m along the length of the drainage collector.

The technical result to which the invention is directed is to determine the filtration state of a soil dam with a cement-cement concrete diaphragm, to determine the locations of possible damage to the clay-cement concrete diaphragm with an accuracy of 1-1.5 m, and to quantify the volume (flow) of water filtration through damage in clay-cement concrete diaphragm, in reducing the time and cost of their detection and elimination.

To achieve the specified technical result, in the method for monitoring the filtration state of a soil dam with an cement-cement concrete diaphragm, including a device from the downstream side of the tubular drainage for collecting water filtered through the dam, and draining the drainage drain into a common water intake manifold, in the process of erecting the soil dam, a waterproof shelf is arranged along the entire filtration front in the lower part of the inverse filter from the side of the downstream of the soil dam, lay a drainage pipe consisting of short sections 1-1.5 m long along the entire filtration front, at a distance from the diaphragm axis within 0.8-1.0 of its width, connect the drain pipe to each local section of the drain pipe and bring each drain pipe into a common viewing loss.

In addition, the claimed decision has an optional feature characterizing its particular case:

- a waterproof shelf, for example, of bentonite mats, is overlapped so that one end is in the area of the cement-cement concrete diaphragm and the other end is led over the drainage pipe.

Distinctive features of the proposed method from the above prototype are the installation of a waterproof shelf along the entire filtration front, for example, from bentonite mats, laying a drainage pipe, at a distance from the axis of the cement-cement concrete diaphragm within 0.8-1.0 of its width, breaking the drainage pipe into short sections 1.0–1.5 m long, connecting a small diameter drain pipe to each local section of the drain pipe, and drain pipes leading to a common viewing loss.

Due to the presence of these signs, a monitoring tool appears that allows direct monitoring of the filtration flow rates in local areas along the entire front of the clay-cement concrete diaphragm, it also makes it possible to identify a section with a high filtration flow rate and determine it with an accuracy of 1.0-1.5 m location. Since all measurements of expenditures are carried out practically in one place, in a special common viewing loss, monitoring can be performed automatically.

The proposed method for monitoring the filtration state of a soil dam with a cement-cement concrete diaphragm is illustrated by the drawings shown in FIG. 1-3.

In FIG. 1 shows a fragment of a soil dam plan.

In FIG. 2 is a fragment of a cross section of a soil dam.

In FIG. 3 - longitudinal profile of the soil dam.

The drawings show a soil dam 1, a cement-concrete diaphragm 2, a return filter 3, a waterproof shelf made of bentonite mats 4, a drain pipe 5, a drain pipe 6, a common viewing hole 7, the upper head - WB, the lower head - NB.

The method is as follows.

To determine the place of damage and the possibility of its control in the cement-cement diaphragm 2 in the lower part of the reverse filter 3 of the soil dam 1 from the NB, prepare the base for a waterproof shelf 4 by cleaning the surface of the base from stones, roots, debris and compacting it, then perform a waterproof shelf 4, for example, by laying bentonite mats so that the side of bentonite mats closest to the axis of the soil dam 1 falls into the area of the cement-cement concrete diaphragm 2. Next, drainage pipes are laid 5 of short sections, for example, 1-1.5 m long and drain pipes 6, plug the drain pipes 5 from both ends, connect drain pipes 6 to each drain section from one side and the total viewing hole 7 from the other. Then fill the laid drainage pipes 5 and drain pipes 6 with the drainage material of the reverse filter 3. Fill and lay the soil manually, ramming, for example, with a vibrating plate, and moistening if necessary.

Thus, the proposed method for monitoring the filtration state of the soil dam 1 with cement-cement diaphragm 2 allows you to control its filtration state, determine the location of damage in the cement-cement diaphragm 2 with an accuracy of 1-1.5 m, the number of leaks that occur, reduce the time and cost of detecting them and eliminating, avoiding the installation of manholes and a drainage collector, and will also allow you to have sound design decisions that can be adapted to soil projects tin with clay-cement-benton diaphragms in various climatic conditions for various designs of clay-cement-benton diaphragms.

The inventive method of monitoring the filtration state of a soil dam with a cement-cement concrete diaphragm has the following limitations: the inapplicability of the method for high-pressure dams, due to the requirement for the strength of the material of the tubular drainage elements, which must withstand the load from the weight of the dam; the restriction on the marking of the laying of the working elements of the method, which are carried out in the lower part of the soil dam, above the level of NB.

Claims (2)

1. A method for monitoring the filtration state of a soil dam with an clay-cement-concrete diaphragm, including a device from the downstream side of the tubular drainage for collecting water filtered through dam 1, and draining the drainage drain into a common water intake manifold, characterized in that a waterproof shelf is arranged during the construction of the soil dam 4 along the entire front of the filtration in the lower part of the inverse filter 3 from the side of the downstream of the soil dam 1, lay a drainage pipe 5, consisting of short sections of length 1-1.5 m along the entire filtration front, at a distance from the axis of the cement-cement concrete diaphragm 2 within the limits of 0.8-1.0 of its width, connect the drain pipe 6 to each local section of the drain pipe 5 and bring each drain pipe 6 into a common viewing I will lose 7. 2. A method for monitoring the filtration state of a soil dam with a cement-cement concrete diaphragm according to claim 1, characterized in that the waterproof shelf 4, for example, of bentonite mats, is overlapped so that one end is in the zone of the cement-cement concrete diaphragm 2 and the other end is led by a drainage pipe 5.

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