SU1521808A1 - Counter-seepage arrangement for earth dam - Google Patents

Abstract

The invention relates to hydraulic structures. The purpose of the invention is to increase the reliability of the device by reducing the output pressure gradients. The impervious device of an earth dam located on an impermeable base consists of a waterproof element 2 and a filter 3 adjacent to its bottom edge. The waterproof element 2 is provided with an impermeable diaphragm 4 connected to the base 1 at the point of contact of the filter 3 and the bottom edge of element 2 and forming with the last angle Θ, equal to 90 ° * 22O * 98A, where α-angle between the lower edge of the impermeable element 2 and the horizontal from the headwaters. The diaphragm 4 may be straight or flexible. The diaphragm 4 can be pivotally connected to the base 1 at the point of contact of the filter 3 and the lower face of the waterproof element 2. 4 Cc. f-ly, 3 ill.

Description

V

 / - {rtsg.2,

The invention relates to hydraulic construction, in particular to the construction of dams from ground materials, and can be applied to the construction of energy, irrigation and waterworks hydroelectric systems, as well as industrial facilities of hydraulic engineering: tailings and accumulators of industrial production.

The purpose of the invention is to improve the operation of the impervious device by reducing the magnitude of the output pressure gradients.

Fig. 1 shows an anti-filter device of a group dam with an impermeable diaphragm made curved, a cross section; 2 is the same with a rectilinear impermeable diaphragm; in FIG. 3 - the same, with a hinged connection of an impenetrable diaphragm with a base.

GG protivotitelitelny device soil dam, located on an impermeable base 1, includes a waterproof element 2 of soil material with a filter 3 on the lower face and an impermeable diaphragm 4 connected to the impermeable base 1 at the point of contact of the feed 3 and the bottom edge of the waterproof element 2 and forming an angle with the latter 0, equal to, where is the angle between the lower edge of the impermeable element 2 and the horizontal from the side of the headwater.

The impermeable diaphragm 4 can be made straight (figure 2 and also Can be connected by a hinge with an impermeable base I at the point of contact of the filter 3 and the bottom face of the impermeable element 2 (figure 3).

The impermeable diaphragm 4 may be made of concrete, reinforced concrete, asphalt concrete, metal sheet, polymeric silt, and other materials.

An impermeable base 1 (diaphragm 4) of an anti-filtration device of a ground dam is considered a base (diaphragm), the ratio of the filtration coefficient of which K (g) to the filtration coefficient of soil of the impermeable element 2 Co

0

five

0

five

0

five

0

five

0

five

is not more than 0.02 (o, 02).

Cd |

The base can be impermeable both as a result of natural genesis, and as a result of engineering impact on it, for example, the design of a concrete slab, fortification cementation, etc.

Protnofiltration device operates as follows.

During the operation of the impervious device, it perceives almost the entire pressure acting on the dam, as a result of which the liquid filters through the waterproof element 2 of ground material. To increase the filtration strength of the soil of the impermeable element 2, filter 3 is arranged along its lower face. Supply of the impermeable element 2 with an impermeable diaphragm 4 connected to impermeable base 1 at the point of contact of filter 3 and the lower face of the impermeable element 2 and forming an angle of 0 with the latter, equal to 90 ° i 9 about 5 where 0 is the angle between the lower edge and the horizontal from the upstream, reduces the value of the output pressure gradients along the lower edge.

Angle 0 is determined by the formula

r sinoi

Y arccos.; k.vigh

where 9 is the angle between the lower edge

waterproof element and impermeable diaphragm;

-h °

I - permissible, according to the conditions

l, 0b1x

the filtration strength of the soil of the impermeable element, the output pressure gradient according to the contact of the impermeable element with an impermeable diaphragm.

The filtration flow, filtering through the impermeable element 2, flows around the impermeable diaphragm 4 and, seeping through the lower edge, enters the filter 3. At the same time, the reorientation of the filtration flow along the impermeable diaphragm 4 in the lower part of the impermeable element 2 reduces the output gradients pressure (Igyx due to a more vertical direction of the filtration flow in the lower edge of the waterproof element 2; a significant decrease in the value

contact output pressure gradient (,) due to the creation of an angle 0 between the impermeable diaphragm 4 and the bottom edge of the impermeable element

k. BULL COS &

I (bases)

K.BWX

since the angle is 0 &; more

that 2, i.e.

sin

coso6

uniform flow of filtration flow along the height of the filter 3 and relative alignment of the output pressure gradients due to more distributed 1 uniform movement of the filtration flow when the water flows to the lower edge of the waterproof element 2; a decrease in the mean pressure gradients in the body of the impermeable element 2 due to the elongation of the length of the current lines as a result of a flow around or an impermeable diaphragm 4.

Claims (4)

Invention Formula . An impervious soil dam device, located on an impermeable base, includes a waterproof element made of soil material with a filter on the lower face, characterized in that, in order to increase the reliability of the anti-filtration device by reducing the output gradient values of the head, my diaphragm, connected to an impermeable base at the point of contact of the filter and the lower face of the impermeable element and forming an acute angle of 9 with the latter, is smaller th oi, where r is the angle between the lower edge of the impermeable element and the horizontal from the headwater. 2. The device according to claim 1, about tl and - that the impermeable diaphragm is made straight in cross section. 3. The device according to Claims 1 and 2, t - characterized by the fact that the impermeable diaphragm is made flexible. 4. A device according to claims 1 to 3, characterized in that the impermeable diaphragm is pivotally connected to the impermeable base at the point of contact of the filter and the bottom face of the water-resistant element. 5, The device according to claims 1-4, about tl and - so that the sharp angle b, smaller angle about, satisfies the condition 0 de 0 oi Aon sinoi arccos-dogg to. BblX  the angle between the bottom edge of the impermeable element and the impermeable diaphragm; the angle between the lower edge of the waterproof element and the horizontal from the upstream; I - permissible under the terms of the filter 1G. OUT soil strength of the impermeable element output pressure gradient according to the contact of the impermeable element with an impermeable diaphragm. SL /////////////// /// /9 ///////// FIG. i l / 77 / Y / / y // y / 7 / fig.Z / /// // 7