A method for pre-grouting reinforcement of surrounding rock of a gate for removing a support in a fully-mechanized coal mining face

Abstract

The application discloses a pre-grouting reinforcement method for surrounding rock of a support-removing passage of a fully-mechanized coal mining face, belongs to the technical field of surrounding rock stability control, and comprises a working face transportation roadway and an air return roadway, grouting holes are arranged in the working face, and the grouting holes on each side are divided into shallow holes, medium-deep holes and deep holes; ultra-fine cement slurry is injected into the working face through the shallow holes, the medium-deep holes and the deep holes, and full penetration of coal and rock bodies is realized; the shallow holes, the deep holes and the medium-deep holes are cross-drilled and grouted; after grouting is completed, corresponding reinforcement structures are formed; after a coal mining support reaches a stop mining line and forms a support-removing passage, the coal wall and the roof are both pre-reinforced coal and rock bodies; on the basis of pre-grouting reinforcement, proper anchor rods and anchor cables are arranged on the coal wall and the roof of the support-removing passage. The application reinforces the coal and rock bodies in the support-removing passage region in advance through advanced pre-grouting, improves the strength and the bearing capacity of the coal and rock bodies in the stop mining line region, and provides a safety guarantee for subsequent safe support removal.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of surrounding rock stability control, and particularly relates to a pre-grouting reinforcement method for a fully mechanized coal mining face support removal channel surrounding rock. BACKGROUND

[0002] In the production of a coal mining face, the handover of the coal mining face is an inevitable link and is a key step for a mine to achieve safe and efficient production. The length of time for the removal of the equipment of the coal mining face restricts the production efficiency of the mine to a certain extent. The non-pre-excavation removal channel technology has problems such as unstable support removal space, easy roof fall of the coal mining face, and easy rib spalling, especially in a broken surrounding rock environment, the safety of the removal of the equipment by using the technology does not meet the standards, and safety accidents are prone to occur.

[0003] In engineering practice, the research on the stability control of the surrounding rock of the non-pre-excavation removal channel is not complete, and the production safety during the removal of the support cannot be guaranteed only by relying on the traditional simple support. Therefore, targeted control measures need to be taken to effectively solve the problem of the stability control of the surrounding rock of the non-pre-excavation removal channel and ensure the basic stability of the surrounding rock of the stop mining line area. SUMMARY

[0004] Therefore, the present application provides a pre-grouting reinforcement method for a fully mechanized coal mining face support removal channel surrounding rock, which is used to solve the above problems.

[0005] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0006] A pre-grouting reinforcement method for a fully mechanized coal mining face support removal channel surrounding rock, comprising:

[0007] a: grouting holes are arranged in the coal mining face from the coal mining face haulage roadway and the air return roadway, the grouting holes on each side are divided into shallow holes, medium-deep holes and deep holes, the reinforcement range of the shallow holes is 1 / 7-1 / 5 of the face width, the reinforcement range of the medium-deep holes is 1 / 4-1 / 2 of the face width, and the reinforcement range of the deep holes is 2 / 5-3 / 5 of the face width;

[0008] b: super-fine cement slurry is injected into the coal mining face through the shallow holes, the medium-deep holes and the deep holes to achieve sufficient penetration of the coal and rock mass;

[0009] c: after the grouting is completed, a corresponding pre-grouting reinforcement structure is formed, after the coal mining support reaches the stop mining line and forms a support removal channel, the coal wall and the roof are both pre-reinforced coal and rock mass;

[0010] d: on the basis of the pre-grouting reinforcement, appropriate anchor rods and anchor cables are arranged on the coal wall and the roof of the support removal channel to further ensure the stability of the surrounding rock of the channel during the removal of the support.

[0011] Further, in a, the angle of shallow hole, medium deep hole and deep hole is adjusted to ensure that the final hole position is above 2.5m-3.0m of the working face mining height, so as to ensure the reinforcement effect of the roof of the subsequent formed support removal channel.

[0012] Further, in a, the grouting holes of the shallow hole, medium deep hole and deep hole are arranged in a quincunx shape, the shallow hole and the deep hole are on the same vertical line, and the medium deep hole is located between the two rows of shallow holes and deep holes.

[0013] Further, the grouting and drilling sequence in a and b is: shallow hole drilling, shallow hole grouting, deep hole drilling, deep hole grouting, medium deep hole drilling, and medium deep hole grouting.

[0014] Further, in b, the water-cement ratio of the ultra-fine cement slurry is controlled at 0.8-1.0, the grouting pressure is adjusted according to the reinforcement depth of the shallow hole, medium deep hole and deep hole, the shallow hole grouting pressure is controlled at 5-8MPa, the medium deep hole grouting pressure is controlled at 8-10MPa, and the deep hole grouting pressure is controlled at 10-12MPa.

[0015] The beneficial effects of the present application are:

[0016] The present application grouts and reinforces the surrounding rock of the stop mining line area in the transportation roadway and the air return roadway on both sides of the working face, on the one hand, the broken coal and rock mass under the influence of the advanced stress is repaired and filled, the integrity and bearing capacity of the coal and rock mass are improved, and the demand for the arrangement of the support removal channel is basically met; on the other hand, the coal and rock mass is reinforced in advance, which creates conditions for the development of subsequent support removal channel support work and reduces the support cost. The present application has good effect on the stability control of the surrounding rock of the support removal channel under the conditions of severe mining, soft coal seam mining and the like, is simple to operate, reasonable in design, and has very high popularization and application value. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0018] Figure 1 is the grouting and reinforcement cross-sectional view of the present application "a method for pre-grouting and reinforcing the surrounding rock of the support removal channel suitable for fully mechanized coal mining face".

[0019] Figure 2 is the grouting hole plan view of the present application "a method for pre-grouting and reinforcing the surrounding rock of the support removal channel suitable for fully mechanized coal mining face".

[0020] Figure 3Is the invention "a method for pre-grouting reinforcement of surrounding rock of a support removal channel suitable for fully mechanized mining face" grouting reinforcement plan view.

[0021] Figure 4 Is the invention "a method for pre-grouting reinforcement of surrounding rock of a support removal channel suitable for fully mechanized mining face" pre-grouting reinforcement effect drawing.

[0022] Figure 5 Is the invention "a method for pre-grouting reinforcement of surrounding rock of a support removal channel suitable for fully mechanized mining face" support removal channel formation effect drawing.

[0023] In the figure:

[0024] 1-transport roadway; 2-return air roadway; 3-shallow hole grouting hole; 4-medium deep hole grouting hole; 5-deep hole grouting hole; 6-coal seam roof; 7-mining coal seam; 8-coal seam floor; 9-pre-grouting reinforcement structure; 10-stopping line; 11-coal mining support; 12-support removal channel; 13-anchor rod; 14-anchor cable. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0026] Referring to the drawings shown in the present application, a method for pre-grouting reinforcement of surrounding rock of a support removal channel suitable for fully mechanized mining face is provided, which comprises: Figures 1-5

[0027] a: From the working face transport roadway 1 and return air roadway 2, grouting holes are arranged in the working face, and each side grouting hole is divided into shallow hole 3, medium deep hole 4 and deep hole 5, wherein the shallow hole 3 reinforcement range is 1 / 7-1 / 5 of the working face width, and the preferred value is 1 / 6 of the working face width; the medium deep hole 4 reinforcement range is 1 / 4-1 / 2 of the working face width, and the preferred value is 1 / 3 of the working face width; the deep hole 5 reinforcement range is 2 / 5-3 / 5 of the working face width, and the preferred value is 1 / 2 of the working face width; the angles of shallow hole 3, medium deep hole 4 and deep hole 5 are adjusted to ensure that the final hole position is 2.5-3.0 m above the working face mining height, so as to ensure the reinforcement effect of the roof of the subsequent support removal channel;

[0028] b: Superfine cement slurry is injected into the working face through shallow hole 3, medium deep hole 4 and deep hole 5 to realize sufficient penetration of coal and rock mass;

[0029] c: After grouting, the corresponding pre-grouting reinforcement structure 9 is formed between the coal seam roof 6, the mining coal seam 7 and the coal seam floor 8, such as Figure 1 ​After the coal mining support 11 reaches the stop line 10 and forms the support removal passage 12, the coal wall and the roof are both pre-reinforced coal and rock mass;

[0030] d: On the basis of pre-grouting reinforcement, proper anchor rods 13 and anchor cables 14 are arranged on the coal wall and the roof of the support removal passage 12, further ensuring the stability of the surrounding rock of the passage during support removal, such as Figure 5 .

[0031] The grouting holes of the shallow holes 3, the medium-depth holes 4 and the deep holes 5 are arranged in a quincunx shape, such as Figure 2 ; the shallow holes 3 and the deep holes 5 are on the same vertical line, and the medium-depth holes 4 are located between the two rows of shallow holes 3 and deep holes 5, such as Figure 3 ; the grouting and drilling sequence is: shallow hole drilling, shallow hole grouting, deep hole drilling, deep hole grouting, medium-depth hole drilling, and medium-depth hole grouting; the main purpose of such arrangement is to test and supplement the grouting effect of the previous group by changing the drilling and grouting of the grouting holes; at the same time, the shallow holes are grouted first to reinforce the shallow surrounding rock, facilitating the application of greater grouting pressure by the medium-depth holes and the deep holes.

[0032] The water-cement ratio of the ultra-fine cement grout is controlled at 0.8-1.0, the grouting pressure is adjusted according to the reinforcement depth of the shallow holes 3, the medium-depth holes 4 and the deep holes 5, the grouting pressure of the shallow holes 3 is controlled at 5-8 MPa, the grouting pressure of the medium-depth holes 4 is controlled at 8-10 MPa, and the grouting pressure of the deep holes 5 is controlled at 10-12 MPa.

[0033] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. For the device disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0034] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for pre-grouting and reinforcing the surrounding rock of a fully mechanized mining face removal passage, characterized in that, include: a: Grouting holes are arranged in the working face from the working face transport roadway (1) and return air roadway (2). Each side of the grouting holes is divided into shallow holes (3), medium-deep holes (4) and deep holes (5). The reinforcement range of shallow holes (3) is 1 / 7 to 1 / 5 of the working face width, the reinforcement range of medium-deep holes (4) is 1 / 4 to 1 / 2 of the working face width, and the reinforcement range of deep holes (5) is 2 / 5 to 3 / 5 of the working face width. b: Inject ultrafine cement slurry into the working face through shallow holes (3), medium-deep holes (4), and deep holes (5) to achieve full penetration into the coal and rock mass; c: After grouting is completed, a corresponding pre-grouting reinforcement structure (9) is formed. After the coal mining support (11) reaches the stop mining line (10) and forms the support removal channel (12), the coal wall and roof are both pre-reinforced coal and rock masses. d: On the basis of pre-grouting reinforcement, appropriate anchor bolts (13) and anchor cables (14) are arranged on the coal wall and roof of the dismantling passage (12) to further ensure the stability of the surrounding rock of the passage during the dismantling process; In a, the grouting holes of shallow holes (3), medium-deep holes (4) and deep holes (5) are arranged in a quincunx pattern. Shallow holes (3) and deep holes (5) are on the same vertical line, and medium-deep holes (4) are located between two rows of shallow holes (3) and deep holes (5). The grouting and drilling sequence in a and b is as follows: shallow hole drilling, shallow hole grouting, deep hole drilling, deep hole grouting, medium-deep hole drilling, and medium-deep hole grouting. In b, the water-cement ratio of ultrafine cement grout is controlled at 0.8~1.

0. The grouting pressure is adjusted according to the reinforcement depth of shallow hole (3), medium-deep hole (4), and deep hole (5). The grouting pressure of shallow hole (3) is controlled at 5~8MPa, the grouting pressure of medium-deep hole (4) is controlled at 8~10MPa, and the grouting pressure of deep hole (5) is controlled at 10~12MPa.

2. The method for pre-grouting and reinforcing the surrounding rock of the fully mechanized mining face removal passage according to claim 1, characterized in that, In a, adjust the angles of shallow hole (3), medium-deep hole (4), and deep hole (5) to ensure that the final hole position falls 2.5m~3.0m above the working face mining height, so as to ensure the reinforcement effect on the top plate of the subsequent removal passage.

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