RU2459084C1 - Method for vertical borehole reconstruction - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: method for vertical borehole reconstruction includes the following stages: mounting of water-proof and backfill formwork, reinforcement mounting, filling of backfill gap between the formwork and borehole lining by compound on the base of aqua-gel and its following displacement by concrete-sand solution. Note that backfill gap is filled through sectoral-perforated pipes structurally included into the metal formwork.

EFFECT: improvement of water-proof properties of borehole lining.

9 cl, 3 dwg

Description

The invention relates to underground construction and could be used in the repair of vertical shafts located in water-saturated rocks, including the reconstruction of underground ventilation shafts.

Reconstruction of a vertical shaft can be done by concreting the lining and injecting hardening mixtures for lining by known methods, for example, according to patents SU 629347, SU 417570, SU 985304, SU 1373822 or SU 1727440 (the closest analogue). However, in conditions of increased groundwater filtration, a rapid repeated destruction of the lining occurs.

The aim of the invention is to increase the waterproofing properties of the lining of the shaft of the mine.

To do this, the method of reconstructing the shaft of a vertical shaft includes installing waterproofing and grouting formwork, mounting working fittings, filling the grouting gap between the formwork and lining the trunk with a solution based on bentonite clay and its subsequent displacement with cement-sand mortar.

As a result, in the existing lining of the trunk, all kinds of embossed voids, microcracks and macrocracks, as well as microcracks in the metal insulation are secured, which guarantees a reliable waterproofing effect.

Decisions based on the wall-in-ground method using bentonite solutions are known in the construction industry. For example, the method according to patent RU 2392383 involves, in particular, a fragment of a trench under a layer of bentonite slurry and its subsequent filling with a concrete mixture according to the method of vertically moving pipes (VPT). However, similar technologies are not described for the purpose of reconstruction of mines and construction of mine shafts.

In a particular case, the installation of a metal waterproofing-grouting formwork is performed using anchor fastening.

In another particular case, the filling of the cement gap is carried out through sectoral-perforated pipes that are included in the cost-effective construction of the metal formwork for supplying solutions.

In another particular case, waterproofing-grouting formwork is additionally tested for tightness by excessive pressure of compressed air.

In another particular case, control of the filling of the grouting gap is carried out through sector-perforated control pipes mounted in waterproofing-grouting formwork with welded fittings with cork taps and monometers, and the drainage water displaced by the solution based on bentonite clay is removed outside the trunk through auxiliary hoses. Flow control makes it possible to exclude unreasonable flow of bentonite solution in the case of, for example, high porosity of the overburden, adjusting the density (volume weight) of the solution in any of the sections of the barrel along its height, increasing the coagulation of particles (fractions) of porous embedding soils.

In another particular case, to fill the grouting gap, a solution based on bentonite clay is periodically pumped, providing complete colmatation of the pores in the lining of the trunk.

In another particular case, the displacement of a solution based on bentonite clay with a cement-sand mortar is carried out by the method of a vertically moving pipe.

In another particular case, the final reinforcing-concrete work is additionally performed on the device of the load-bearing reinforced concrete shell by means of several successive calls.

The invention is illustrated by drawings.

Figure 1 is a longitudinal section of a ventilation shaft.

Figure 2 is a section aa of the ventilation shaft.

Figure 3 is an enlarged image of section I of Figure 2.

The invention can be implemented as follows. Two diametrically located sectoral-perforated pipes 2 for supplying solutions and two diametrically located sectorally-perforated control pipes 3 with welded fittings with plug valves and pressure gauges are mounted from the work sites of the rack scaffolding 1 pre-installed in the ventilation shaft. The metal waterproofing and grouting formwork 4 is installed using anchor fastening 5. Next, by grids, by electric welding in a checkerboard pattern, the external working reinforcement 6 of the reinforcing cage of the trunk sheath is mounted with a connection to the formwork. To check welds before pouring a solution of bentonite clay, waterproofing and grouting formwork 4, using pressure gauges, are tested for leaks with an excess pressure of compressed air of not more than 0.001 MPa. The filling of the cement gap 7 between the formwork 4 and the lining 8 of the shaft of the mine with a solution of bentonite clay is produced through sectorally perforated pipes 2 until the solution appears through welded fittings in the upper part of the sectorally perforated pipes 3 of the control. In this case, the drainage water constantly displaced by the bentonite clay solution is removed outside the shaft of the mine through auxiliary hoses, which, after filling the grouting gap 7, are also used to periodically pump the bentonite clay solution until the absorption ceases and all pores in the lining of the barrel 8 are completely clogged, in production ) soils and petrified solutions from injection. The effectiveness of colmatization is determined by the volume of consumption of bentonite clay, taking into account the difference between the volume of the prepared solution and the volume of the cavity, determined by the results of the executive survey. Using a vertically moving pipe method, the bentonite clay solution is displaced with a cement-sand mortar (Portland cement and fine sand composition 1: 2). In this case, the solution of bentonite clay is not completely removed from the cracks and pores, but partially settles on the entire lining 8 of the barrel and formwork 4 due to adhesion and is compacted, creating a reliable waterproofing effect. After holding the cement-sand mortar for 10 days, the final reinforcement-concrete work on the installation of the load-bearing reinforced concrete shell is carried out by several successive calls, each of which includes the reinforcement of the reinforcing cage, fixing the mobile formwork and concreting.

Thus, the invention provides the following advantages and additional technical results:

- additional effect of metal insulation;

- increases the bearing capacity of the inner reinforced concrete shell due to the inclusion in the supporting structure of waterproofing and grouting formwork of working and distribution valves;

- eliminates the work on the preliminary elimination of the cap, cracks, caverns, repair of the primary waterproofing, including stamping of joints and replacement of the waterproofing of washers in bolted joints and plugs for primary and control injection, it is only necessary to remove debris from the cells in the tubing lining and only eliminate (if any) suffusion (removal) of soil, leaving drainage of water;

- mutual corrosion protection of metal waterproofing and grouting formwork is provided, on the one hand, with a bentonite clay film, and on the other hand, with a reinforced concrete shell of the barrel jacket, and at the same time, the reinforced concrete shell is protected from water access to its reinforcing cage, excluding its corrosion;

- increases the waterproofing effect of the metal waterproofing and grouting formwork due to the exothermic process of the cement-bentonite mixture when the reinforced concrete shell is installed, i.e. the bentonite clay film on the formwork is drained, thereby eliminating or at least reducing the galvanic process that contributes to the corrosion of the metal waterproofing and grouting formwork;

- eliminates the need for additional gidrofobiziruyuschih funds to cover the surfaces of the metal waterproofing and grouting formwork.

Claims (9)

1. The method of reconstruction of the shaft of a vertical shaft includes installing waterproofing and grouting formwork, mounting reinforcement, filling the grouting gap between the formwork and lining the trunk with a solution based on bentonite clay and its subsequent displacement with cement-sand mortar. 2. The method according to claim 1, characterized in that the installation of metal waterproofing and grouting formwork is performed using anchor fastening. 3. The method according to claim 1, characterized in that the waterproofing-grouting formwork is additionally tested for tightness by excessive pressure of compressed air. 4. The method according to claim 1, characterized in that the filling of the cement gap is carried out through sectorally-perforated pipes for constructing solutions incorporated in the metal formwork. 5. The method according to claim 1, characterized in that they control the filling of the grouting gap through sectoral-perforated control pipes mounted in waterproofing-grouting formwork with welded fittings with plug valves and monometers. 6. The method according to claim 4, characterized in that the displaced water displaced by the solution based on bentonite clay is removed to the outside of the barrel through auxiliary hoses. 7. The method according to claim 1, characterized in that by filling the grout gap with a solution based on bentonite clay, a solution based on bentonite clay is periodically pumped. 8. The method according to claim 1, characterized in that the displacement of the cement-sand mortar of a solution based on bentonite clay is carried out by the method of vertically moving pipes. 9. The method according to claim 1, characterized in that it further includes final reinforcing-concrete work on the device of the load-bearing reinforced concrete shell by several successive calls.

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