Point-column mining method based on permanent point-column reinforcement and permanent point-column reinforcement structure

Abstract

The present invention discloses a point column mining method based on permanent point column reinforcement and a permanent point column reinforcement structure, which performs stability analysis on a point column mining area, selects permanent point columns that need to be reinforced, obtains the dominant structural surface occurrence and properties of the permanent point columns through engineering geological survey and exploration analysis; reinforces the permanent point columns once according to the dominant structural surface occurrence and properties of the permanent point columns, and arranges a plurality of stress gauges around the permanent point columns during the one-time reinforcement process; mines the point columns in the point column mining area that have been reinforced, monitors the stress evolution law of the permanent point columns through stress gauges, and performs secondary reinforcement on the permanent point columns if it is monitored that the stress value borne by the permanent point columns exceeds the warning value; achieves the reinforcement of the permanent point columns with less materials, saves the reinforcement cost, effectively avoids the problem of point column reinforcement failure, and greatly improves the safety of the mining operation area.

Description

Technical Field

[0001] The invention relates to the technical field of mine recovery, and in particular to a point column recovery method based on permanent point column reinforcement and a permanent point column reinforcement structure. Background Art

[0002] The comprehensive mining method is to advance the working face along the strike or inclination of the ore body, leaving irregular point pillars to maintain the goaf during the mining process. Due to the country's requirements for green mine construction and to ensure the safe mining of deep resources in mines, it is necessary to use the subsequent filling method to treat the upper goaf. The number of high-grade point pillars left by the comprehensive mining method in the past is considerable, and the economic benefits are obvious. It is a pity to abandon them. At the same time, this part of the income can also alleviate the filling investment. On the other hand, it can improve the resource recovery rate and reduce the dependence on foreign resources. In the process of point pillar mining, in order to ensure the safety of mining, the permanent point pillars are usually reinforced. At present, the method of reinforcing permanent point pillars is usually to wrap a layer of concrete around the permanent point pillars indiscriminately. This reinforcement method is expensive, and due to the indiscriminate support of permanent point pillars, it is easy to cause excessive reinforcement strength of permanent point pillars. Secondly, during the point column mining process, mining a part of the point columns will inevitably cause stress redistribution, increasing the stress concentration phenomenon of the permanent point columns. When the stress in the permanent point columns far exceeds their own strength, the permanent point column reinforcement failure will occur. The previous reinforcement methods did not have any monitoring and early warning methods for this. The reinforcement was blind and lacked scientificity, making it difficult to guide the safe mining of point columns.

[0003] The patent application with application number CN202110784909.0 adopts a technical solution to provide a method for supporting, reinforcing and recovering point columns in a mining area. The technical solution is: using long anchor cables to support and reinforce the point columns, the lower part of the anchor cables is fixed, and the upper part is tightened and fixed to ensure that the point columns always have sufficient support for the roof of the mining area during the mining period, thereby ensuring the safety of the roof during the mining period. It discloses the safe recovery of recyclable point columns, but does not consider the redistribution of stress in the mine during the recovery of recyclable point columns, resulting in stress concentration of permanent point columns. The stress bearing capacity of permanent point columns is less than their supporting stress, which makes it easy to cause the risk of collapse during the mining of point columns.

[0004] In view of this, there is an urgent need to provide a point-column mining method that can avoid the problem of excessive reinforcement strength and improve the safety of the mining operation area. Summary of the invention

[0005] In order to overcome the deficiencies in the existing field of mine recovery technology, the present invention provides a point column recovery method based on permanent point column reinforcement and a permanent point column reinforcement structure, which can not only avoid the problem of excessive reinforcement strength, but also improve the safety of the recovery operation area.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: to provide a point column mining method based on permanent point column reinforcement, which comprises the following steps:

[0007] Conduct stability analysis on the point-pillar mining area, select the permanent point pillars that need to be reinforced, and obtain the dominant structural surface occurrence and properties of the permanent point pillars through engineering geological survey and exploration analysis;

[0008] According to the dominant structural surface of the permanent point column and its properties, the permanent point column is reinforced once, and multiple stress gauges are set around the circumference of the permanent point column during the reinforcement process;

[0009] The point columns in the point column mining area that have completed reinforcement are mined, and the stress evolution law of the permanent point columns is monitored by stress gauges. If the stress value of the permanent point column is monitored to exceed the warning value, the permanent point column is reinforced for the second time.

[0010] Preferably, after obtaining the dominant structural surface attitude and properties of the permanent point column, the deformation and failure form of the permanent point column is predicted according to the dominant structural surface attitude and properties of the permanent point column, and a corresponding reinforcement method is selected for the permanent point column according to the deformation and failure form of the permanent point column.

[0011] Preferably, the deformation and failure forms of the permanent point column include splitting tensile failure and shear failure:

[0012] If the deformation and failure mode of the permanent point column is predicted to be splitting tensile failure according to the orientation and properties of the dominant structural surface of the permanent point column, the permanent point column is reinforced at the middle position of the dominant structural surface;

[0013] If the deformation and failure form of the permanent point column is predicted to be splitting tensile failure based on the occurrence and properties of the dominant structural surface of the permanent point column, the permanent point column is reinforced at the upper and lower ends of the dominant structural surface respectively.

[0014] Preferably, the method of reinforcing the advantageous structural surface position of the permanent point column specifically includes the following steps:

[0015] The permanent point column is reinforced once, specifically, a circle of concrete reinforcement is poured around the permanent point column at the middle position of the dominant structural surface of the permanent point column, and while pouring the concrete reinforcement, a plurality of stress gauges are arranged in the concrete around the permanent point column;

[0016] According to the numerical detection of the stress gauge, it is determined whether to carry out secondary reinforcement;

[0017] If it is monitored that the stress value of the permanent point column exceeds the warning value, the permanent point column is reinforced for the second time, specifically, a concrete thickening portion is poured again around the permanent point column on the outside of the concrete reinforcement portion.

[0018] Preferably, the steps of pouring the concrete reinforcement part and the concrete thickening part are as follows:

[0019] The first pouring height is 0.2-0.3m, and the second pouring is carried out after initial setting. The subsequent pouring height is 0.5m each time.

[0020] Preferably, the method of reinforcing the advantageous structural surface position of the permanent point column specifically includes the following steps:

[0021] The permanent point column is reinforced once, specifically, a circle of concrete reinforcement is poured around the permanent point column at the middle position of the dominant structural surface of the permanent point column, and while pouring the concrete reinforcement, a plurality of stress gauges are arranged in the concrete around the permanent point column;

[0022] According to the numerical detection of the stress gauge, it is determined whether to carry out secondary reinforcement;

[0023] If it is monitored that the stress value of the permanent point column exceeds the warning value, the permanent point column will be reinforced for the second time, specifically by using tension anchor rods to transversely penetrate the concrete reinforcement part and the permanent point column, and using locks to tension the protruding ends of the tension anchor rods.

[0024] Preferably, when the concrete reinforcement part is poured to half the height, a plurality of stress gauges are installed in the concrete at equal intervals around the permanent point column, and then the concrete is poured until the specified height.

[0025] A permanent point column reinforcement structure, characterized in that it is used to reinforce the permanent point columns in the above-mentioned point column recovery method based on permanent point column reinforcement, and the permanent point column reinforcement structure includes a concrete casting mold, a pulling component, a rib component and a support member; the concrete casting mold circumferentially surrounds the outer side of the permanent point column dominant structural surface, and its lower end is inserted into an annular groove opened around the permanent point column at the lower end of the permanent point column dominant structural surface, and its upper end is fixed by pulling by the pulling component to form a concrete casting space arranged in an annular manner around the permanent point column dominant structural surface; the rib component is arranged in the concrete casting space, and the support member is supported under the concrete casting mold.

[0026] Preferably, the concrete casting mold is an L-shaped mold, and the lower end of the L-shaped mold is sealed and clamped with the annular groove through a rubber seal.

[0027] Preferably, the pulling component includes multiple groups of pulling anchor rods and steel cables, and the multiple pulling anchor rods are circumferentially distributed and embedded in the upper end of the permanent point column dominant structural surface. One end of the steel cable is connected to the pulling anchor rod, and the other end is connected to the upper end of the L-shaped mold.

[0028] The beneficial effects of the present invention are:

[0029] The point column mining method based on permanent point column reinforcement described in the present invention obtains the dominant structural surface occurrence and properties of the permanent point column through engineering geological survey, exploration and analysis, and only reinforces the dominant structural surface position of the permanent point column according to the dominant structural surface occurrence and properties, thereby achieving the reinforcement of the point column with less material, saving reinforcement costs, and avoiding the problem of excessive point column reinforcement strength caused by indiscriminate support.

[0030] The present invention arranges a plurality of stress gauges around the permanent point column during the primary reinforcement process, thereby achieving real-time monitoring of the stress evolution law of the permanent point column during the point column recovery process. When it is monitored that the stress value borne by the permanent point column exceeds the warning value, the permanent point column can be promptly reinforced for a second time, thereby effectively avoiding the problem of point column reinforcement failure and greatly improving the safety of the recovery operation area.

[0031] The pouring range of the concrete thickening part described in the present invention is determined according to the monitoring data of the stress gauge. When the stress value monitored by a certain stress gauge or multiple stress gauges exceeds the warning value, the concrete thickening part is reinforced only outside the partial orientation indicated by the stress gauge or multiple stress gauges in the concrete reinforcement part, so as to further save the reinforcement cost of the permanent point column. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the structural position of the one-time reinforcement of the permanent point column according to an embodiment of the present invention.

[0033] Figure 2 It is a schematic diagram of the structural status of the permanent point column reinforcement structure according to an embodiment of the present invention.

[0034] Figure 3 It is a schematic diagram of another structural state of the permanent point column reinforcement structure according to an embodiment of the present invention.

[0035] Figure 4 This is a schematic diagram of the structural position of the secondary reinforcement of the permanent point column according to an embodiment of the present invention.

[0036] The markings of the components in the accompanying drawings are as follows:

[0037] 1. L-shaped mold; 11. Rubber seal; 2. Pulling component; 21. Pulling anchor rod; 22. Steel cable; 3. Rib component; 4. Diagonal bracing steel pipe; 5. Strain gauge; 6. Annular groove; 7. Concrete reinforcement part; 8. Concrete thickening part. DETAILED DESCRIPTION

[0038] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0039] The embodiment of the present invention provides a point column mining method based on permanent point column reinforcement, which comprises the following steps:

[0040] S1. Conduct stability analysis on the point-column mining area, select the permanent point columns that need to be reinforced, and obtain the dominant structural surface occurrence and properties of the permanent point columns through engineering geological survey and exploration analysis.

[0041] Firstly, the stability of the point-pillar mining area is analyzed through theoretical calculation and numerical simulation. Firstly, some point pillars are determined as permanent point pillars, and then the permanent point pillars that need to be reinforced are selected for reinforcement. Then, a detailed engineering geological survey is carried out on the permanent point pillars to analyze their strength, structural surface development degree, etc., and the dominant structural surface occurrence and properties of the permanent point pillars are obtained through analysis.

[0042] After obtaining the dominant structural plane occurrence and properties of the permanent point column, the deformation and failure forms of the permanent point column are predicted according to the dominant structural plane occurrence and properties of the permanent point column. The deformation and failure forms of the permanent point column include splitting tensile failure and shear failure:

[0043] If the deformation and failure mode of the permanent point column is predicted to be splitting tensile failure according to the occurrence and properties of the dominant structural surface of the permanent point column, the permanent point column is reinforced in the middle of the dominant structural surface, such as Figure 1 (a) shown.

[0044] If the deformation failure form of the permanent point column is predicted to be splitting tensile failure based on the occurrence and properties of the dominant structural surface of the permanent point column, the permanent point column is reinforced at the upper and lower ends of the dominant structural surface, such as Figure 1 (b) as shown.

[0045] According to the deformation and failure form of the permanent point column, the corresponding reinforcement method is selected for the permanent point column, that is, the permanent point column is reinforced once according to the dominant structural surface occurrence and properties of the permanent point column, and the stress evolution law of the permanent point column is monitored. If the stress value of the permanent point column is monitored to exceed the warning value, the permanent point column is reinforced twice; the specific steps are as follows:

[0046] S2. Reinforce the permanent point column once according to the occurrence and properties of the dominant structural surface of the permanent point column; specifically, cast a circle of concrete reinforcement part 7 around the permanent point column in the middle position of the dominant structural surface of the permanent point column.

[0047] The concrete reinforcement part 7 is formed by pouring a permanent point column reinforcement structure. Figure 2As shown, the permanent point column reinforcement structure includes a concrete casting mold, a pulling component 2, a rib component 3 and a support member; the concrete casting mold circumferentially surrounds the outer side of the permanent point column dominant structural surface, and its lower end is inserted into an annular groove 6 opened around the permanent point column at the lower end of the permanent point column dominant structural surface to form a bottom seal, and its upper end is pulled and fixed by the pulling component 2 to form a concrete casting space arranged in a ring around the permanent point column dominant structural surface; the rib component 3 is arranged in the concrete casting space, and the support member is supported under the concrete casting mold.

[0048] like Figure 2 and Figure 3 As shown, the concrete casting mold is an L-shaped mold 1, which is arranged around the permanent point column. A rubber seal 11 is mounted on the lower end of the L-shaped mold 1. The width of the rubber seal 11 is slightly larger than the width of the annular groove 6. Therefore, the lower end of the L-shaped mold 1 is set in the annular groove 6 through the rubber seal 11 by interference fit, thereby forming a sealed clamping connection to prevent concrete from overflowing from the lower end of the L-shaped mold 1. The upper end of the L-shaped mold 1 is fixed by a pulling component 2. The pulling component 2 includes a plurality of pulling anchor rods 21 and a steel cable 22. The plurality of pulling anchor rods 21 are circumferentially distributed and embedded in the upper end of the dominant structural surface of the permanent point column. One end of the steel cable 22 is connected to the pulling anchor rod 21, and the other end is connected to the upper end of the L-shaped mold 1. The rib component 3 is built into the concrete casting space formed between the L-shaped mold 1 and the column wall of the permanent point column to provide higher strength for the concrete casting body. The support member is a diagonal brace steel pipe 4, one end of which is supported on the ground, and the other end is supported below the L-shaped mold 1.

[0049] In the process of pouring the concrete reinforcement part 7 using the permanent point column reinforcement structure, the first pouring height is 0.2-0.3m, and the second pouring is carried out after initial setting, and the pouring height each time thereafter is 0.5m; and when the concrete reinforcement part 7 is poured to half the height, a plurality of stress gauges 5 are installed in the concrete at equal intervals around the circumference of the permanent point column, and then the concrete pouring is continued until the specified height, that is, the pouring work of the concrete reinforcement part 7 is completed, and the permanent point column is reinforced once.

[0050] The height and thickness of the concrete reinforcement part 7 are set according to the distribution of the dominant structural surface of the permanent point column.

[0051] S3. Mining the point columns in the point column mining area that has completed reinforcement, and monitoring the stress evolution law of the permanent point columns. If it is monitored that the stress value of the permanent point columns exceeds the warning value, the permanent point columns are reinforced for the second time.

[0052] After the permanent point column is reinforced once, the point column in the point column mining area is mined. During the point column mining process, only the unreinforced point column is mined. At the same time, the stress evolution law of the permanent point column is monitored in real time by the pressure gauge built into the concrete reinforcement part 7. According to the value monitoring of the stress gauge 5, it is determined whether to perform secondary reinforcement.

[0053] If it is monitored that the stress value borne by the permanent point column exceeds the warning value, the permanent point column will be reinforced for a second time. Specifically, the concrete thickening part 8 can be poured around the circumference of the permanent point column again on the outside of the concrete reinforcement part 7. The pouring range of the concrete thickening part 8 is determined according to the monitoring data of the stress gauge 5. When the stress value monitored by a certain stress gauge 5 or multiple stress gauges 5 exceeds the warning value, the concrete thickening part 8 is reinforced only outside the partial position indicated by the stress gauge 5 or multiple stress gauges 5 in the concrete reinforcement part 7, so as to further save the reinforcement cost of the permanent point column. If all the stress gauges 5 surrounding the permanent point column exceed the warning value, a circle of concrete thickening part 8 is poured outside the concrete reinforcement part 7 to increase the stress bearing capacity of the permanent point column, such as Figure 4 shown.

[0054] The pouring method of the concrete thickening part 8 is consistent with the pouring method of the concrete reinforcement part 7, that is, the L-shaped mold 1 is circumferentially surrounded on the outside of the concrete reinforcement part 7, and its lower end is inserted into the annular groove 6 opened around the lower end of the concrete reinforcement part 7 and its body, and the bottom seal is formed by the interference fit of the rubber seal 11, and its upper end is pulled and fixed on the permanent point column by the steel cable 22, forming a concrete pouring space surrounding the concrete reinforcement part 7; the rib component 3 is arranged in the concrete pouring space, and the support member is supported under the L-shaped mold 1.

[0055] In the process of pouring the concrete thickening part 8 using the permanent point column reinforcement structure, the first pouring height is 0.2-0.3m, and the second pouring is carried out after initial setting. Thereafter, the pouring height is 0.5m each time until the specified height is reached, completing the pouring of the concrete thickening part 8 and realizing secondary reinforcement of the permanent point column.

[0056] In addition, the permanent point column can be reinforced for a second time by using tension anchor rods, specifically, the tension anchor rods are transversely passed through the concrete reinforcement part 7 and the permanent point column, and the protruding ends of the tension anchor rods are tensioned by using locks, thereby achieving secondary reinforcement of the permanent point column.

[0057] The point column mining method based on permanent point column reinforcement described in the present invention obtains the dominant structural surface occurrence and properties of the permanent point column through engineering geological survey, exploration and analysis, and only reinforces the dominant structural surface position of the permanent point column according to the dominant structural surface occurrence and properties, thereby achieving the reinforcement of the permanent point column with less material, saving reinforcement costs, and avoiding the problem of excessive point column reinforcement strength caused by indiscriminate support; in addition, the stress evolution law of the permanent point column is monitored in real time during the point column mining process, and when it is monitored that the stress value borne by the permanent point column exceeds the warning value, the permanent point column is promptly reinforced for a second time, which effectively avoids the problem of point column reinforcement failure and greatly improves the safety of the mining operation area.

[0058] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A point column mining method based on permanent point column reinforcement, characterized in that: The steps include: Conduct stability analysis on the point-pillar mining area, select the permanent point pillars that need to be reinforced, and obtain the dominant structural surface occurrence and properties of the permanent point pillars through engineering geological survey and exploration analysis; According to the dominant structural surface of the permanent point column and its properties, the permanent point column is reinforced once, and multiple stress gauges are set around the circumference of the permanent point column during the reinforcement process; The point columns in the point column mining area that have completed reinforcement are mined, and the stress evolution law of the permanent point columns is monitored by stress gauges. If the stress value of the permanent point column is monitored to exceed the warning value, the permanent point column is reinforced for the second time.

2. The point column mining method based on permanent point column reinforcement according to claim 1 is characterized in that: After obtaining the dominant structural surface occurrence and properties of the permanent point column, the deformation and failure forms of the permanent point column are predicted according to the dominant structural surface occurrence and properties of the permanent point column, and the corresponding reinforcement method is selected for the permanent point column according to the deformation and failure forms of the permanent point column.

3. The point column mining method based on permanent point column reinforcement according to claim 1 is characterized in that: The method of reinforcing the advantageous structural surface position of the permanent point column specifically includes the following steps: The permanent point column is reinforced once, specifically, a circle of concrete reinforcement is poured around the permanent point column at the middle position of the dominant structural surface of the permanent point column, and while pouring the concrete reinforcement, a plurality of stress gauges are arranged in the concrete around the permanent point column; According to the numerical detection of the stress gauge, it is determined whether to carry out secondary reinforcement; If it is monitored that the stress value of the permanent point column exceeds the warning value, the permanent point column is reinforced for the second time, specifically, a concrete thickening portion is poured again around the permanent point column on the outside of the concrete reinforcement portion.

4. The point column mining method based on permanent point column reinforcement according to claim 3 is characterized in that: The steps of pouring the concrete reinforcement part and the concrete thickening part are as follows: The first pouring height is 0.2-0.3m, and the second pouring is carried out after initial setting. The subsequent pouring height is 0.5m each time.

5. The point column mining method based on permanent point column reinforcement according to claim 1 is characterized in that: The method of reinforcing the advantageous structural surface position of the permanent point column specifically includes the following steps: The permanent point column is reinforced once, specifically, a circle of concrete reinforcement is poured around the permanent point column at the middle position of the dominant structural surface of the permanent point column, and while pouring the concrete reinforcement, a plurality of stress gauges are arranged in the concrete around the permanent point column; According to the numerical detection of the stress gauge, it is determined whether to carry out secondary reinforcement; If it is monitored that the stress value of the permanent point column exceeds the warning value, the permanent point column will be reinforced for the second time, specifically by using tension anchor rods to transversely penetrate the concrete reinforcement part and the permanent point column, and using locks to tension the protruding ends of the tension anchor rods.

6. The point column mining method based on permanent point column reinforcement according to claim 3 or 5, characterized in that: When the concrete reinforcement part is poured to half the height, a plurality of stress gauges are installed in the concrete at equal intervals around the circumference of the permanent point column, and then the concrete is poured continuously until the designated height.

7. A permanent point column reinforcement structure, characterized in that: Used to reinforce the permanent point columns in the point column recovery method based on permanent point column reinforcement as described in any one of claims 1 to 5, the permanent point column reinforcement structure includes a concrete casting mold, a pulling component, a rib component and a support member; the concrete casting mold circumferentially surrounds the outer side of the dominant structural surface of the permanent point column, and its lower end is inserted into an annular groove opened around the circumference of the permanent point column at the lower end of the dominant structural surface of the permanent point column, and its upper end is fixed by pulling by the pulling component to form a concrete casting space arranged in an annular manner around the dominant structural surface of the permanent point column; the rib component is arranged in the concrete casting space, and the support member is supported under the concrete casting mold.

8. The permanent point column reinforcement structure according to claim 7 is characterized in that: The concrete pouring mold is an L-shaped mold, and the lower end of the L-shaped mold is sealed and clamped with the annular groove through a rubber seal.

9. The permanent point column reinforcement structure according to claim 7, characterized in that: The pulling component includes multiple groups of pulling anchor rods and steel cables. Multiple pulling anchor rods are circumferentially distributed and embedded in the upper end of the permanent point column advantageous structural surface. One end of the steel cable is connected to the pulling anchor rod, and the other end is connected to the upper end of the L-shaped mold.

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