SU1283402A1 - Rock consolidating method - Google Patents

Abstract

The invention relates to mining and improves the quality of hardening of rocks and productivity. The volume of the fractured hollowness of the mass that is required to be reinforced is preliminarily determined. Then borehole 1 of a certain length is drilled. In the wellbore part of the well 1, an expanding compound (PC) 3 is placed in the shell 4 beyond the boundary of the reinforced zone 2. Then a hardening solution is fed into the well 1 and the mouth is sealed. Under the action of the pressure generated in the well PC, the strengthening composition is pressed into the cracks. The hardening of the hardening composition begins when the entire volume of cracks in zone 2 is filled with a fully expanded PC in the shell. The increase in the volume of PC is taken equal to the volume of cracks of the reinforced array. Borehole volume. wells 1 outside zone 2 are assumed to be equal to the volume of PC, 2 Il. (L

Description

tvd

CX)

with

IN9

one

The invention relates to mining and can be used in work aimed at improving the stability of underground structures and mine workings.

The aim of the invention is to increase labor productivity and the quality of hardening of rocks. Fig. 1 shows the layout of the spreading and strengthening compositions in the well; Fig. 2 shows a model for carrying out the method.

The method is carried out as follows.

834022

Then, a strengthening composition 5, for example, 1SHU-328 or 11PU-329, is supplied to well 1. After that, the well is sealed at the mouth, HanpHi -sep, sealed with an GT-45 6; After performing the above operations, the crushing of the reinforcement composition into the cracks occurs under the action of pressure created in the well by the expanding fO composition in the moving shell, and the reinforcement composition hardens when it fills the entire volume of cracks in the reinforced zone 2

Pre-known methods

(e.g., rheometry) determine the amount of fissure void mass to be strengthened. Then determine the depth of the well, designed to implement the method

L 1 + I, + 1

3

de 1 - depth of the reinforced zone

thirty

rock formations

1 - the length of the well for an hour

the boundary of the reinforced zone, the volume of which is equal to the volume of cracks in the reinforced zone;

1 - the initial length of the part of the well beyond the boundary of the reinforced zone, in which the expanding composition is located, the increase in the volume of which is 35 degrees equal to the volume of the cracks of the reinforced mountain massif. breeds

20

five

1 3t 1 C -}

g

where 3) is the volume of cracks of the reinforced array, rel, unit ,;

R is the radius of the reinforcement zone, cm;

g - well radius, cm. From the drilling of a well 1 with a length L, In the wellbore part l of the well {the expanding composition 3 is placed in the shell 4 outside the zone to be strengthened. 2 The shell may be elastic, stretchable, or rigid, View of a canister with a movable lid acting as a piston. Expanding composition 3 is, for example, a water-sand-cement mixture with an addition of aluminum powder or a Bristar type expanding cement solution.

Example. For the tests, a model (Fig. 2) of a well in the form of a pipe 1, 2 m long, 56 mm in diameter, was made of plexiglas tightly closed

on the one hand a stopper 7, with the valve 8 - on the other hand. The radius of the reinforced zone R is 0.25 m, the depth of the fixed zone is 1, 1.0 m, the relative volume of fracture hollowness is 0.006. Then the length of the well

1, beyond the boundary of the reinforced zone, the volume of which is equal to the volume of cracks, is equal to

v.2

12 J - 0.006: 100

, 25-25.,. -578 --- 278- - 1) 47 cm.

Expanded cuts 3 consisted of a water-cement mixture with the addition of aluminum powder in the ratio of components B: P: C: A 1.5: 3.1: 0.5. The expanding composition 3 in the shell 4, which was used as an air rubber ball, occupied part of the pipe with a spacing of I, 52 cm. Thus, the total length of the well

five

0

five

L 1. + I,

1, 100 + 47 + 52 199 cm.

A composition based on a carbamide-formaldehyde resin KF-W with a hardener — oxalic acid and a filler — sand in a ratio of 1: 1: 0.04, was used as a hardening agent.

The volume of cracks was modeled by a section of the same pipe 9, tightly closed on one side and connected to the valve 8, the length of this pipe is 50 cm.

At the end of the well model, sheath 4 was placed with expanding composition 3, then the remaining part of pipe 1 was filled with reinforcing composition 5 and

3

: akriipli valve 8, to which is connected the pipe 9, which simulates the volume of cracks.

The composition in the shell began to expand 10 minutes after its preparation, i.e. it must be placed in the well for 10 minutes. Expansion ended after 30 minutes. In this case, the reinforcement composition 5 was extruded into the 9-crack model. At the end of the expansion, the composition in the shell began to harden and, 60 minutes after its preparation, was a rigid porous cylinder. Strengthening compound 5 filled the model of 9 cracks, compressing the water in it. Full hardening of the hardening composition occurred after 24 hours, while it was an elastic cylinder.

In order to place in the well an expanding composition in the shell (strengthening composition) and is closed with its stopper (sealing), i.e. It took 3 min to carry out the work requiring the availability of equipment and labor costs. At the prepared site, the injection of the fortifying agent into the system occurs automatically without the human being’s fate.

The proposed method allows, in comparison with the prototype, to strengthen the rocks around the excavation with better quality, eliminating the use of anchors, ensuring their solidity by forcing a reinforcing composition into the cracks, which fills the entire volume of the cracks existing in the massif (this creates a supporting structure from the reinforced ). In addition, during slow injection of the reinforcement composition into the cracks, the possibility of ejecting the reinforcement composition during reverse hydraulic impact is eliminated, while the expansion composition and its shell during the entire expansion time perform the function (artificial injection pump, and after the increase in their volume the function of a locking device ensuring that the created pressure in the well is retained until the contacts completely solidify in the cracks JO J5 0

0

five

na In addition, there is no need to use the injection pump park to fill the fractures of the massif with a hardening compound. The completion of the wellbore part beyond the boundary of the reinforced zone with a volume equal to the volume of the expanding composition, and the expansion of the expanding (retracting) shell with the expanding composition, the amount of which will ensure the expansion (increase) of the volume to a predetermined volume of fractures rocks, will allow strengthening the most disturbed part of the marginal rock mass by filling the entire volume of cracks in this zone with a hardening composition, which also increases the degree of chneni rock mass. The reinforcement composition remaining in the well is a polymeric anchor of solid construction, additionally fastening the array in the depth of the reinforcement zone. Moreover, the adhesion ability of the anchor to the rocks is enhanced due to the connection of the hardened reinforcement composition in the array fractures. The polymer anchor can be reinforced.

Claims (1)

Invention Formula A method of strengthening rocks, including drilling wells, injecting a hardening solution in them, sealing the well at the wellhead and creating pressure in the well, characterized in that, in order to increase the productivity of labor and the quality of the hardening of rocks, the pressure in the well creates an expandable composition placed in the shell, which is installed in the well bore zone before the injection of a strengthening solution into it beyond the boundary of the reinforced zone of rocks, while the increase in the volume of the expanding composition is taken equal to the volume of cracks of the reinforced rock mass, and the volume of the near-wellbore part beyond the boundary of the reinforced zone is equal to the volume of the expanded composition. . :: Yal1: | h-sg- - ud-d  CfH / 8.2