A "110 method" advanced support method for fully-mechanized coal mining face

Abstract

The application discloses a kind of "110 method" advanced support method of fully mechanized face, comprising the following steps: S1, using anchor cable and steel band to carry out strengthening support to leave lane, and leave lane advanced support is completed support work before working face mining, S2, working face roof cutting pre-splitting is carried out to transport crossheading, and pre-splitting is carried out in advance, S3, short cantilever beam structure is formed between transport crossheading and working face roof, the beneficial effects of the application are: the advanced support of fully mechanized face is changed from traditional passive support to active support, which simplifies the advanced support of fully mechanized face, realizes the stability of the advanced support of fully mechanized face, optimizes the advanced support of fully mechanized face, reduces the corresponding production cost input of advanced support during production, solves the problem of anchor cable damage of roadway advanced support, cancels the investment of advanced support equipment, reduces the construction cost and labor input of additional anchor cable, and improves work efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of advanced support, and specifically to an advanced support method for the fully mechanized mining face of the "110 mining method". Background Technique

[0002] For the fully mechanized mining face of the "110" mining method, two gateways are designed and arranged. One of the gateways is reserved as a roadway after the mining of this working face, and it also serves as the transportation gateway for the next fully mechanized mining face. The gateway designed to be reserved adopts technological techniques such as roof strengthening support, roof cutting pre-splitting, gangue retaining support, and strengthening support for the reserved roadway section. Currently, during the mining of the fully mechanized mining face, the gateway of the fully mechanized mining face is designed to be supported by an advanced hydraulic support group. The overlap of the support positions is inevitably generated between the advanced support combined with the advanced support of the fully mechanized mining equipment and the bolts and cable bolts with straps that meet the strengthening support strength of the reserved roadway. During the mining process of the fully mechanized mining face, problems such as the advanced support damaging the roof bolts and cable bolts of the roadway have occurred.

[0003] Under the existing technological conditions, since the advanced support of the fully mechanized mining face repeatedly supports the roof as the fully mechanized mining face is pushed forward, on the one hand, the nut of the roof strengthening support bolt (cable bolt locking device) and the tray are squeezed by the support roof beam, resulting in the failure of the bolt (cable bolt), and damaging the mechanical structure between the bolt (cable bolt) for strengthening the support of the reserved roadway and the surrounding rock; on the other hand, in order to ensure the support strength of the reserved roadway, the damaged bolts (cable bolts) must be further installed, increasing the corresponding engineering cost; at the same time, due to the repeated support of the gateway roof, it is not conducive to the safety management of the roadway roof. Summary of the Invention

[0004] The purpose of the present invention is to provide an advanced support method for the fully mechanized mining face of the "110 mining method" to solve the problem that the repeated support of the gateway roof is not conducive to the safety management of the roadway roof as proposed in the above background technique.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An advanced support method for the fully mechanized mining face of the "110 mining method", including the following steps:

[0006] S1. Strengthen the support of the reserved roadway by using cable bolts and straps, and complete the support work before the mining of the working face;

[0007] S2. Perform roof cutting pre-splitting on the working face roof of the transportation gateway, and implement pre-splitting in advance;

[0008] S3. Form a short cantilever beam structure between the transportation gateway and the working face roof;

[0009] S4. Calculate the support strength of the advanced support according to the working resistance of the advanced support supporting the medium-thick coal seam, calculate the support strength of the cable bolt;

[0010] S5. Conduct theoretical verification on the cable bolt support and strap support to meet the requirements of the advanced support strength.

[0011] As a preferred embodiment of the present invention: the cross-section of the steel strip is W-shaped, and the steel strip is a low-carbon steel strip material.

[0012] As a preferred embodiment of the present invention, the transport roadway is a full coal roadway.

[0013] As a preferred embodiment of the present invention: the anchor cable in S1 is provided with two steel strands for cooperation, the nominal diameter of the two steel strands is 21.8-25mm, the length of one steel strand is 10-11m, the length of the other steel strand is 9-10m, and the preload of the two steel strands is not less than 379-400kN.

[0014] As a preferred embodiment of the present invention: the width of the steel strip in S1 is 220-240mm, and the thickness of the steel strip in S1 is 5-10mm.

[0015] As a preferred embodiment of the present invention: the depth of the slit hole in the top pre-splitting in S2 is 8.5-10m, and the angle between the top cutting hole in the working face direction and the plumb line direction is 10-20°.

[0016] As a preferred embodiment of the present invention: the height of the pre-cracked working face of the top plate of the working face in S2 is greater than 100-150m.

[0017] As a preferred embodiment of the present invention, the specific operational steps for forming the short cantilever beam structure in step S3 are as follows:

[0018] S31. On the basis of strengthening the support of the roadway and implementing pre-splitting in advance, implement roof cutting and pre-splitting in advance at the working face;

[0019] S31. The structure between the transport roadway and the top plate of the working face is destroyed to form a short cantilever beam structure.

[0020] As a preferred embodiment of the present invention: the support strength of the advanced support calculated based on the working resistance of the advanced support in the medium-thick coal seam in S4 is 0.133-0.2 MPa, and the support strength of the anchor cable calculated based on the support strength of the anchor cable is 0.131-0.2 MPa, and the difference between the support strength of the advanced support and the support strength of the anchor cable is small.

[0021] As a preferred embodiment of the present invention: the theoretical verification in S5 is a Protodyakonov theoretical verification, and the specific operation steps of the Protodyakonov theoretical verification are as follows:

[0022] S51. A pressure arch will form above the tunnel to bear the weight of the overlying rock strata above the arch.

[0023] S52. The maximum load on the tunnel support is determined by the weight of the rock inside the arch.

[0024] S53. Obtain the maximum load value on the roadway support;

[0025] S54. The obtained maximum load value is compared and processed with the advance support strength requirement.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention simplifies the pre-support of fully mechanized mining faces by transforming it from traditional passive support to active support, and achieves the stability of pre-support of fully mechanized mining faces. By optimizing the pre-support of fully mechanized mining faces, the corresponding production cost input for pre-support during production is reduced. The problem of leaving the roadway with reinforced support anchor cables after the pre-support of the roadway is damaged is solved, the investment in pre-support equipment is eliminated, the construction cost and labor input of re-installing anchor cables are reduced, and the work efficiency is improved. Detailed Implementation

[0027] This invention provides a technical solution: a method for advance support of a fully mechanized mining face using the "110 method", comprising the following steps:

[0028] S1. Anchor cables and steel strips are used to reinforce the roadway support. The advance support of the roadway is completed before the working face is mined.

[0029] S2. Pre-crack the top plate of the working face of the transport roadway by cutting and cracking the top plate in advance;

[0030] S3. A short cantilever beam structure is formed between the transport roadway and the top plate of the working face, which reduces the production cost of advance support during production.

[0031] S4. Based on the working resistance calculation of the advanced support for medium-thick coal seams, calculate the support strength of the advanced support and the support strength of the anchor cable.

[0032] S5. Theoretical calculations were performed on anchor cable support and steel strip support to meet the strength requirements of advance support. The advance support of fully mechanized mining face was transformed from traditional passive support to active support, which simplified the advance support of fully mechanized mining face.

[0033] The steel strip has a W-shaped cross-section and is made of low-carbon steel.

[0034] Among them, the transport roadway is a coal roadway, which has a lower cost per linear meter compared to the traditional coal and rock roadway, thus reducing construction costs.

[0035] The anchor cable in S1 is equipped with two steel strands for coordination. The nominal diameter of the two steel strands is 21.8-25mm. One steel strand is 10-11m long and the other steel strand is 9-10m long. The preload of the two steel strands is not less than 379-400kN.

[0036] The width of the steel strip in S1 is 220-240mm, and the thickness of the steel strip in S1 is 5-10mm.

[0037] In S2, the depth of the pre-splitting cut hole is 8.5-10m, and the angle between the pre-splitting cut hole towards the working face and the plumb line is 10-20°. This limitation on the depth of the pre-splitting cut hole improves the stability of the support.

[0038] In S2, the height of the pre-cracked top plate of the working face is greater than 100-150m. The pre-cracked top plate of the working face is restricted, which improves the stability during processing.

[0039] The specific operational steps for forming the short cantilever beam structure in S3 are as follows:

[0040] S31. On the basis of strengthening the support of the roadway and implementing pre-splitting in advance, implement roof cutting and pre-splitting in advance at the working face;

[0041] S31. The structure between the transport roadway and the top plate of the working face is disrupted to form a short cantilever beam structure, which reduces the corresponding production cost of advance support during production and improves the strength of the support.

[0042] In S4, the support strength of the advanced support calculated based on the working resistance of the advanced support in medium-thick coal seams is 0.133-0.2 MPa, and the support strength of the anchor cable calculated based on the support strength is 0.131-0.2 MPa. The small difference between the support strength of the advanced support and the support strength of the anchor cable improves the strength of the support.

[0043] Among them, the theoretical verification in S5 is the Protodyakonov theory verification, and the specific operation steps of the Protodyakonov theory verification are as follows:

[0044] S51. A pressure arch will form above the tunnel to bear the weight of the overlying rock strata above the arch.

[0045] S52. The maximum load on the tunnel support is determined by the weight of the rock inside the arch.

[0046] S53. Obtain the maximum load value on the roadway support;

[0047] S54. The obtained maximum load value is compared and processed with the advance support strength requirement. The comparison and processing of the values ​​determines whether the advance support strength requirement is met, which improves work efficiency.

[0048] Example 1: A method for advance support of a fully mechanized mining face using the "110 method", comprising the following steps:

[0049] S1. Anchor cables and steel strips are used to reinforce the roadway support. The steel strip has a W-shaped cross-section, is made of low-carbon steel strip, has a width of 220mm, and a thickness of 5mm. The anchor cable is equipped with two steel strands for coordination. The nominal diameter of the two steel strands is 21.8mm. One steel strand is 10m long and the other is 9m long. The preload of the two steel strands is not less than 379kN. The roadway advance support is completed before the working face is mined.

[0050] S2. Pre-crack the top plate of the working face of the transport roadway by cutting the top plate, with a cutting hole depth of 8.5m. The pre-cracking is carried out in advance, and the angle between the top cutting hole in the direction of the working face and the plumb line is 10°.

[0051] S3. Based on the reinforcement of the roadway and the pre-splitting of the working face, the roof of the working face will be pre-cut and pre-splitting will be carried out in advance to destroy the structure between the transport roadway and the roof of the working face to form a short cantilever beam structure. The height of the roof pre-splitting of the working face is more than 100m ahead of the working face.

[0052] S4. Based on the calculation of the working resistance of the advanced support for medium-thick coal seams, the support strength of the advanced support is calculated to be 0.133 MPa. The support strength of the anchor cable is calculated to be 0.131 MPa. The difference between the support strength of the advanced support and the support strength of the anchor cable is small.

[0053] S5. Protodyakonov's theory is used to verify the anchor cable support and steel strip support. A pressure arch will be formed in the upper part of the roadway, which will bear the weight of the overlying rock layer above the arch. The maximum load on the roadway support is determined by the weight of the rock inside the arch. The maximum load value on the roadway support is obtained. The obtained maximum load value is compared with the strength requirement of the advance support. After comparison, the strength requirement of the advance support is met.

[0054] Example 2: A method for advance support of a fully mechanized mining face using the "110 method", comprising the following steps:

[0055] S1. Anchor cables and steel strips are used to reinforce the roadway support. The steel strip has a W-shaped cross-section, is made of low-carbon steel strip, has a width of 240mm, and a thickness of 10mm. The anchor cable is equipped with two steel strands for coordination. The nominal diameter of the two steel strands is 25mm. One steel strand is 11m long and the other is 10m long. The preload of the two steel strands is not less than 400kN. The roadway advance support is completed before the working face is mined.

[0056] S2. Pre-crack the top plate of the working face of the transport roadway by cutting the top plate of the working face. The cutting hole depth is 10m. Pre-cracking is carried out in advance. The angle between the top cutting hole in the direction of the working face and the direction of the plumb bob is 20°.

[0057] S3. Based on the reinforcement of the roadway and the pre-splitting of the working face, the roof of the working face will be pre-cut and pre-splitting will be carried out in advance to destroy the structure between the transport roadway and the roof of the working face to form a short cantilever beam structure. The height of the roof pre-splitting of the working face is more than 150m ahead of the working face.

[0058] S4. Based on the calculation of the working resistance of the advanced support for medium-thick coal seams, the support strength of the advanced support is calculated to be 0.2 MPa. The support strength of the anchor cable is calculated to be 0.2 MPa. The difference between the support strength of the advanced support and the support strength of the anchor cable is small.

[0059] S5. Protodyakonov's theory is used to verify the anchor cable support and steel strip support. A pressure arch will be formed in the upper part of the roadway, which will bear the weight of the overlying rock layer above the arch. The maximum load on the roadway support is determined by the weight of the rock inside the arch. The maximum load value on the roadway support is obtained. The obtained maximum load value is compared with the strength requirement of the advance support. After comparison, the strength requirement of the advance support is met.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for advance support of a fully mechanized mining face using the "110 method", characterized in that, Includes the following steps: S1. Anchor cables and steel strips are used to reinforce the roadway support. The advance support of the roadway is completed before the working face is mined. S2. Pre-crack the top plate of the working face of the transport roadway by cutting and cracking the top plate in advance; S3. A short cantilever beam structure is formed between the transport roadway and the top plate of the working face; S4. Based on the calculation of the working resistance of the advanced support for medium-thick coal seams, calculate the support strength of the advanced support and the support strength of the anchor cable, and analyze the difference between the support strength of the advanced support and the support strength of the anchor cable. S5. Theoretical calculations were performed on anchor cable support and steel strip support to ensure they meet the strength requirements for advanced support.

2. The "110 method" fully mechanized mining face advance support method according to claim 1, characterized in that: The steel strip has a W-shaped cross-section and is made of low-carbon steel strip.

3. The "110 method" fully mechanized mining face advance support method according to claim 2, characterized in that: The transport roadway is a coal-only roadway.

4. A method for advance support of a fully mechanized mining face using the "110 method" as described in claim 3, characterized in that: The anchor cable in S1 is provided with two steel strands for cooperation. The nominal diameter of the two steel strands is 21.8-25mm. The length of one steel strand is 10-11m and the length of the other steel strand is 9-10m. The preload of the two steel strands is not less than 379-400kN.

5. A method for advance support of a fully mechanized mining face using the "110 method" as described in claim 4, characterized in that: The width of the steel strip in S1 is 220-240mm, and the thickness of the steel strip in S1 is 5-10mm.

6. A method for advance support of a fully mechanized mining face using the "110 method" as described in claim 5, characterized in that: The depth of the pre-splitting cut hole in S2 is 8.5-10m, and the angle between the pre-splitting cut hole towards the working face and the plumb bob direction is 10-20°.

7. A method for advance support of a fully mechanized mining face using the "110 method" as described in claim 6, characterized in that: In S2, the height of the pre-cracked top plate of the working face ahead of the working face is greater than 100-150m.

8. A method for advance support of a fully mechanized mining face according to claim 7, characterized in that: The specific operational steps for forming the short cantilever beam structure in S3 are as follows: S31. On the basis of strengthening the support of the roadway and implementing pre-splitting in advance, implement roof cutting and pre-splitting in advance at the working face; S32. The structure between the transport roadway and the top plate of the working face is destroyed to form a short cantilever beam structure.

9. A method for advance support of a fully mechanized mining face according to claim 8, characterized in that: The support strength of the advanced support in S4, calculated based on the working resistance of the advanced support in medium-thick coal seams, is 0.133-0.2 MPa, and the support strength of the anchor cable, calculated based on the anchor cable support condition, is 0.131-0.2 MPa. The difference between the support strength of the advanced support and the support strength of the anchor cable is small.

10. A method for advance support of a fully mechanized mining face according to claim 9, characterized in that: The theoretical verification in S5 is the Protodyakonov theory verification. The specific operation steps of the Protodyakonov theory verification are as follows: S51, a pressure arch will be formed in the upper part of the tunnel to bear the weight of the overlying rock layer above the arch. S52. The maximum load on the tunnel support is determined by the weight of the rock inside the arch. S53. Obtain the maximum load value on the roadway support; S54. The obtained maximum load value is compared and processed with the advance support strength requirement.