SU859541A1 - Drainage apparatus of underground concrete lined water duct - Google Patents

Description

one

The invention relates to groundwater drainage devices and is intended for discharging their facing from groundwater pressure. It can be used in the construction of underground pressure steel pipelines, which are concreted in underground workings and which are under pressure from hydrocarbonate underground waters, for example, tunnels and turbine conduits of a hydroelectric station, a hydroelectric station, and for other purposes.

Known drainage devices of underground water lines, including drains of various designs 1.

Closest to the invention is a drainage device for an underground water conduit with a concrete lining, including drilling drills and collectors 2.

The main disadvantage of all known structures of drainage drains is susceptibility to chemical spuding (in the presence of unfavorable hydrochemical conditions), which results in reduced drainage flow rates, reduced its service life, due to "overgrowing of bore holes with precipitated carbonate salts.

There are various methods for cleaning from sediments and restoring drainage performance: hydraulic, mechanical, explosive, chemical, etc. Recently, ultrasound and electro-hydraulic effect have been used for this purpose.

However, these cleaning methods in most cases have a negative effect on the further operation of the drainage system, for example, during chemical exposure of the sediment, or in some cases

10 drainage structures cannot find practical application.

These drawbacks reduce the reliability of the device, as well as the durability of the conduit and drainage.

The purpose of the invention is to increase the reliability of operation and increase the durability of the conduit and drainage.

The goal is achieved by the fact that each drill hole is provided with a pipe 20 installed in its internal cavity, one end of which is fixed in a concrete lining, and the other end is equipped with a sealing lip located on its external surface, the length of the pipe can be 1 / 2-1 / 6 from the length of the drill hole.

FIG. 1 shows a drainage device, a general view in cross section; in fig. 2 — node I in FIG. one; in fig. 3 - node II in FIG. one; in fig. 4 is a diagram illustrating the operation of the device.

The drainage device of the conduit 1, located in the underground excavation 2 and molded with rock 3 by concrete lining 4, has transverse annular collector pipes 5 connected to longitudinal collector pipes 6 and radial shpurovny drains 7. In the internal cavity of each of the drains 7, pipes 8 are installed sealing cuffs 9.

The transverse annular manifold pipes 5 on both sides contain welded nozzles 10 and 11. The nozzle 10 serves to connect with the pipeline 1, and a nozzle 11 for mounting the pipes 8. A plug 12 is installed along the nozzle 10 and 11 axis in the pipeline to block the process mounting hole. The nozzle 11 has a thread at its end, on which with the aid of a bobbin 13 it is screwed on a nozzle 14 with a sleeve 15 sealed at its end. The coupling has a flange 16 with a gasket 17. At the inner surface, the coupling 15 has a thread into which the sleeve 18 is screwed. with a pipe 8 welded to it. The length of the pipe 8 is chosen from the condition that it corresponds to 1 / 3-1 / 6 of the length of the drain. As the material of the cuff take foam rubber, fiberglass, glass wool, slag, etc.

Mount the drainage device as follows.

The main components of the structure, namely, pipeline 1, transverse and longitudinal collector pipes 5 and 6 with nozzles 10 and 11, are pre-assembled, assembled and wrapped. In addition, using flange 13, a flange 16 with a gasket 17 and coupling is installed close to the rock 15. It should be noted that at the beginning of the installation the flange 15 is not drilled. After assembling all of the above elements and concreting, the drains are set up.

A conduit pipe (not shown) with a length exceeding the thickness of facing concrete by about 0.2 m, with an external thread, at the end facing the rock, under the thread on the coupling is inserted through the opening in the pipeline 1 through the pipes 10, 11 and 14. 15. Screw the conduit pipe into the sleeve 15 until the not drilled flange is secured 16. After that, the drill machine shank is introduced into the conductor pipe, the flange 16 is drilled with a gasket 17 and then drilled 7 of a given length are drilled in the rock. The conductor tube is not only for

properly guiding the drill rod, but also to protect the drainage pipes from clogging up with drill cuttings.

After removal of the conductor tube, a tube 8 with a cuff 9 is inserted into the drain 7,

fixed at the end of the pipe, and rotating

the sleeve 18, screw it in the sleeve 15 to

emphasis in the flange 16. In this form, the drainage device is ready for operation.

The device works as follows.

Underground waters penetrate the concrete of the lining 4 and form in it a saturated solution of calcium hydroxide calcium (OH). From the concrete lining this solution along the lines of 20 diffuses through the rock 3 inside

drains 7. The water in the rock around the drain 7 and inside it contains aggressive carbon dioxide CO, which can flow into the groundwater, as well as from the air through collector pipes 5 and 6

(if they are not completely filled with water). This carbon dioxide reacts chemically with the above-mentioned calcium oxide hydrate, following the reaction.

Ca (OH) 2 + COjHiO CaCOj + 2HaO (1) The particles of calcium carbonate (calcium carbonate) CaCO3 formed during this reaction are practically insoluble and precipitate.

In the presence of calcium carbonate (Calcium bicarbonate) Ca (HCO3) g (also known to have good solubility in water) in groundwater filling the rock 3 and drain 7, calcium (as is well known, it has good water solubility), a reaction will also occur. Ca (OH) 2 + Ca (HCO3) and 2CaCO3 + 2HiO The insoluble calcium carbonate particles formed during this reaction, CaCO3, gradually fill not only the pores and cracks in rock 3 near drain 7, but also the cavity between pipe 8 and the walls of the drain 7. So there is a slow natural tampon of this cavity. The sealing cuff 9 serves, first, to ensure that on the descending drains the precipitating CaCOj particles do not fall into the working section of the drain 7 (between the cuff 9 and the bottom of the well forming

5 Drenu 7), secondly, that in arbitrarily tilted drains 7, the drained water would by its own flow not carry CaCOj particles, which are very small, into drainage pipes 5 and 6 that divert water beyond the limits of pipeline 1.

0 At the end of the first period of drainage operation, as a result of the chemical clogging described above, insoluble salts fill space 19 (shown by square hatching in Fig. 4 b) between the sleeve 8 and the walls of the drain 7 and the cavity of pores and cracks in the zone of rock and concrete in the vicinity of drains 7. A slow natural tamponage of space occurs, as it were. 19.

Due to this, in the subsequent period of drainage operation, the diffusion resistance between the concrete 4 and the working section of the drain 7 (the cavity between the bottom of the borehole and the cuff 9) increases significantly because the area is impermeable to diffusion. At the same time, the intensity of salt deposition decreases sharply and, accordingly, the estimated duration of salt driving in the working section of the drain 7, estimated for many hundreds of years, as shown by an approximate hydrochemical calculation.

The cuff 9 should weakly pass water in the direction of the axis of the well forming the drain 7 so that, due to the water drained by the well section, speed up the process of driving with insoluble salts, firstly, the cavity between the pipe 8 and the walls of the well, secondly, then cracks in concrete and rock in zone 19. Along with a weak permeability of the cuff 9 for water, it must be impermeable to small particles of insoluble salts so that they do not block the working area of the well from its bottom to the cuff 9. Then two satisfied t Kie materials such as fiberglass, glass, schlakovata, foam and so on. n.

Thus, the main purpose of the pipes installed in the drainage and the pipes installed in the concrete lining will be fulfilled, i.e., to increase the diffusion resistance by lengthening the current lines through which the substances forming a saturated solution occur and cause the formation of insoluble salts that clog drains .

Claims (2)

1. The drainage device of an underground water conduit with a concrete lining, including radial shcherovy drains and collectors, characterized in that, in order to increase the reliability of operation and increase the durability of the conduit and drainage, each shaft drain is fitted with a pipe installed in its internal cavity, one end of which fixed in a concrete lining, and the other is provided with a sealing lip located on its outer surface. 2. A device according to claim 1, characterized in that the length of the pipe is 1 / 3-1 / 6 of the length of the drill rod. Sources of information taken into account in the examination 1- Directions on the design of drainage of underground hydraulic structures, veins 045-72, 1973, p. 10-14. 2. Well bore drainage and anti-filtration cementation in underground hydraulic structures. Issue 61, M., “Energie, 1978, p. 20. L - 0 and .- Q. 0 - ° ..- o% -: oj -o-o. o o - I-o ... ":;:.; /. Ltd/. . °, O --- °: P-: -O SO - ° - o С .о .0. -o -.0- -o-oh - oh - oh - about 0- ° -. ° ° -o,, 0.0 -o - X o -.0; .o. o d o o - .0 L O. -0. 0 ° - o to.-O-. o °. o - o. 0. °, oh, oh ... ° o. but. -. loi about; o- o: ° . - - - - About O S. -; o-- / -v ° - "... - о. «.-, 9 .о -, -.„ - о.-о; about -. ° ,.about-. :. |; -; .: 1 -. ° b °: -: ° s FIG.