CN114575845B - Method for checking width of explosion-proof isolation coal pillar in room-pillar overhead goaf - Google Patents

Method for checking width of explosion-proof isolation coal pillar in room-pillar overhead goaf Download PDF

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CN114575845B
CN114575845B CN202210199629.8A CN202210199629A CN114575845B CN 114575845 B CN114575845 B CN 114575845B CN 202210199629 A CN202210199629 A CN 202210199629A CN 114575845 B CN114575845 B CN 114575845B
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pillar
explosion
goaf
width
room
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CN114575845A (en
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程海星
朱磊
徐凯
刘成勇
吴玉意
刘文涛
黄剑斌
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China Coal Energy Research Institute Co Ltd
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21CMINING OR QUARRYING
    • E21C41/00Methods of underground or surface mining; Layouts therefor
    • E21C41/16Methods of underground mining; Layouts therefor
    • E21C41/18Methods of underground mining; Layouts therefor for brown or hard coal

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Abstract

The invention relates to the field of coal mine safety, in particular to a house-column type overhead goaf explosion-proof isolation coal pillar width checking method. The method is a new checking method for judging whether the width of the explosion-proof isolation coal pillar of the room and column type overhead goaf can meet the safety requirement or not under the condition of unknown conditions, and can effectively prevent underground casualties, roadways and equipment damage caused by shock waves generated by sudden large-area collapse of the room and column type overhead goaf.

Description

Method for checking width of explosion-proof isolation coal pillar in room-pillar overhead goaf
Technical Field
The invention relates to the field of coal mine safety, in particular to a house-column type overhead goaf explosion-proof isolation coal pillar width checking method.
Background
In the initial stage of mining of partial small coal mines, a room and pillar type mining method is mostly adopted, and a room and pillar type overhead goaf with a wide range is formed. Due to the fact that the reserved coal pillar is narrow in size, under the effect of long-term overlying strata load, the strength of the coal pillar is weakened gradually, the coal pillar is easy to be unstable and damaged, large-area caving of a suspended roof goaf is caused, the phenomenon of ore vibration frequently occurs, and the local ecological environment and coal mine safety production are greatly damaged. Because the local village and town coal mine technology and management level fall behind, mining data are not timely embodied in drawings, when the house and column type roof-hanging disaster is treated, only the house and column type mining range and main mining parameters (for example, the mining of 6 meters is reserved for 8 meters) can be often determined, the specific coal house and coal column distribution condition is often unknown, and the house and column type roof-hanging disaster is treated with obstacles. Under the condition, a house-column type overhead goaf explosion-proof isolation coal pillar width checking method needs to be established to judge whether the house-column type overhead goaf threatens the safety of the existing production system.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a house-column type overhead goaf explosion-proof isolation coal pillar width checking method.
The invention is realized by the following technical scheme:
a house column type overhead goaf explosion-proof isolation coal pillar width checking method comprises the following steps:
Step 1, determining the range, parameters and the width of an explosion-proof isolation coal pillar of a room-pillar overhead goaf;
And 2, setting that only one roadway is communicated between the room and column type overhead goaf and the explosion-proof isolation coal pillar, judging whether the width of the explosion-proof isolation coal pillar meets the safety requirement, and when the explosion-proof isolation coal pillar is broken by the shock waves formed after the room and column type overhead goaf collapses, judging that the width of the explosion-proof isolation coal pillar does not meet the safety requirement, otherwise, judging that the width of the explosion-proof isolation coal pillar meets the safety requirement.
Preferably, roadway parameters of communication between the room and pillar overhead goaf and the explosion-proof isolation coal pillar are obtained according to the parameters of the room and pillar overhead goaf.
Preferably, the room column type overhead goaf is in an overhead state, and the explosion-proof isolation coal column tightly wraps the edge of the room column type overhead goaf to form a sealing wall for isolating the room column type overhead goaf from the existing production system.
Further, the stress of the sealing wall formed by the explosion-proof isolating coal pillar is calculated, and the calculation formula is as follows:
Wherein P represents the air impact load applied to the tunnel sealing wall and MPa; k represents a loss coefficient of the wind flow velocity moving in the wind path, represents energy loss when wind flow reaches the closed wall from the goaf through a series of roadways, and is 0.1-0.5 according to the communication condition of the closed wall and the collapse area; a represents the caving area of the goaf roof, m 2; p represents the coal seam mining rate; ρ represents the air density, kg/m 3; g represents the acceleration of gravity, kg/m 3; m represents coal seam mining height/M; s represents the roadway cross-sectional area, m 2.
Further, the judging method of the width safety requirement of the explosion-proof isolation coal pillar is to check the shearing damage criterion and check the bending damage criterion of the width of the explosion-proof isolation coal pillar in sequence, and when the width colleague of the explosion-proof isolation coal pillar meets the checking of the shearing damage criterion and the checking of the bending damage criterion, the judging method judges that the width of the explosion-proof isolation coal pillar meets the safety requirement.
Furthermore, the calculation formula of the shearing damage criterion for the width of the explosion-proof isolation coal pillar is as follows:
Wherein m represents the width of the sealing wall, and m; h represents the height of the sealing wall, m; d represents the thickness of the sealing wall, m; [ τ j ] represents the shear strength of the sealing wall, pa; p represents the air impact load applied to the tunnel sealing wall and MPa; s represents the roadway cross-sectional area, m 2.
Further, the calculation formula of the bending failure criterion for the width of the explosion-proof isolation coal pillar is as follows:
Wherein lambda represents a coefficient, and the value is taken according to an internal force coefficient table of the four-side simple support plate under the action of uniformly distributed load and the length-width ratio of the combined plate; [ τ w ] represents the tensile strength of the sealing wall and Pa; d represents the thickness of the sealing wall, m; p represents the air impact load applied to the tunnel sealing wall and MPa; h represents the height of the sealing wall and m.
Preferably, when the number of the roadways between the room and pillar type overhead goaf and the explosion-proof isolation coal pillar is larger, the impact of the impact wave formed after the room and pillar type overhead goaf collapses on the explosion-proof isolation coal pillar is smaller, and otherwise, the impact of the impact wave formed after the room and pillar type overhead goaf collapses on the explosion-proof isolation coal pillar is larger.
Compared with the prior art, the invention has the following beneficial technical effects:
The invention provides a house-column type overhead goaf explosion-proof isolation coal pillar width checking method, which is used for checking by determining the house-column type overhead goaf range and main mining parameters and effectively judging whether the explosion-proof isolation coal pillar width meets the safety requirement or not under the condition that the distribution condition of concrete coal houses and coal pillars is unknown. The method is a new checking method for judging whether the width of the explosion-proof isolation coal pillar of the room and column type overhead goaf can meet the safety requirement or not under the condition of unknown conditions, and can effectively prevent underground casualties, roadways and equipment damage caused by shock waves generated by sudden large-area collapse of the room and column type overhead goaf.
Drawings
FIG. 1 is a flow chart of a method for checking the width of an explosion-proof isolating coal pillar in a room-pillar overhead goaf;
FIG. 2 is a schematic diagram of a distribution structure of a room-pillar overhead goaf and an explosion-proof isolation coal pillar in the invention;
FIG. 3 is a schematic diagram of the distribution structure of the explosion-proof isolation coal pillar under the most unfavorable working condition in the room-pillar overhead goaf.
Detailed Description
In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention is described in further detail below with reference to the attached drawing figures:
Referring to fig. 1, in one embodiment of the present invention, a method for checking the width of an explosion-proof isolating coal pillar in a roof-stud overhead goaf is provided, including the following steps:
Step 1, determining the range, parameters and the width of an explosion-proof isolation coal pillar of a room-pillar overhead goaf;
Step 2, setting that only one roadway is communicated between a room and column type overhead goaf and an explosion-proof isolation coal pillar, judging whether the width of the explosion-proof isolation coal pillar meets the safety requirement, and when the explosion-proof isolation coal pillar is broken by shock waves formed after the room and column type overhead goaf collapses, judging that the width of the explosion-proof isolation coal pillar does not meet the safety requirement and other safety reinforcement measures are needed; otherwise, judging that the width of the explosion-proof isolation coal pillar meets the safety requirement.
Specifically, roadway parameters of communication between the room and pillar overhead goaf and the explosion-proof isolation coal pillar are obtained according to the parameters of the room and pillar overhead goaf.
Specifically, the room column type overhead goaf is in an overhead state, and the explosion-proof isolation coal column tightly wraps the edge of the room column type overhead goaf to form a sealing wall for isolating the room column type overhead goaf from the existing production system, as shown in fig. 2.
Under the condition that the distribution condition of the coal house and the coal pillar is unknown, in the most unfavorable working condition, only one roadway is communicated with the isolation coal pillar in the overhead goaf, the room-pillar mining parameters are assumed to be m meters, n meters are reserved (namely, the width of the coal house is m meters, the width of the coal pillar is n meters), the mining height is h meters, the roadway clear width communicated with the overhead goaf can be obtained to be m meters, the clear height is h meters, and if the room-pillar overhead goaf suddenly collapses in a large area, the formed shock wave can not break the isolation coal pillar through the roadway, so that the width of the isolation coal pillar can be judged to meet the safety requirement. The most adverse operating conditions are shown in fig. 3.
Specifically, the stress of the sealing wall formed by the explosion-proof isolating coal pillar is calculated, and the calculation formula is as follows:
Wherein P represents the air impact load applied to the tunnel sealing wall and MPa; k represents a loss coefficient of the wind flow velocity moving in the wind path, represents energy loss when wind flow reaches the closed wall from the goaf through a series of roadways, and is 0.1-0.5 according to the communication condition of the closed wall and the collapse area; a represents the caving area of the goaf roof, m 2; p represents the coal seam mining rate; ρ represents the air density, kg/m 3; g represents the acceleration of gravity, kg/m 3; m represents coal seam mining height/M; s represents the roadway cross-sectional area, m 2.
Specifically, the method for judging the safety requirement of the width of the explosion-proof isolation coal pillar comprises the steps of checking the shearing damage criterion of the width of the isolation coal pillar and checking the bending damage criterion of the width of the explosion-proof isolation coal pillar in sequence, and judging that the width of the explosion-proof isolation coal pillar meets the safety requirement when the width colleague of the explosion-proof isolation coal pillar meets the checking of the shearing damage criterion and the checking of the bending damage criterion.
The calculation formula of the shearing damage criterion for the width of the explosion-proof isolation coal pillar is as follows:
Wherein m represents the width of the sealing wall, and m; h represents the height of the sealing wall, m; d represents the thickness of the sealing wall, m; [ τ j ] represents the shear strength of the sealing wall, pa; p represents the air impact load applied to the tunnel sealing wall and MPa; s represents the roadway cross-sectional area, m 2.
The calculation formula of the bending damage criterion for the width of the explosion-proof isolation coal pillar is as follows:
Wherein lambda represents a coefficient, and the value is taken according to an internal force coefficient table of the four-side simple support plate under the action of uniformly distributed load and the length-width ratio of the combined plate; [ τ w ] represents the tensile strength of the sealing wall and Pa; d represents the thickness of the sealing wall, m; p represents the air impact load applied to the tunnel sealing wall and MPa; h represents the height of the sealing wall and m.
When the number of the roadways between the room and pillar type overhead goaf and the explosion-proof isolation coal pillar is larger, the impact of the shock wave formed after the room and pillar type overhead goaf on the explosion-proof isolation coal pillar is smaller, otherwise, the impact of the shock wave formed after the room and pillar type overhead goaf is larger on the explosion-proof isolation coal pillar.
Therefore, when only one roadway is communicated between the room and pillar overhead goaf and the explosion-proof isolation coal pillar, the impact of the impact wave formed after the room and pillar overhead goaf collapses on the explosion-proof isolation coal pillar is larger as the most unfavorable working condition, and when the width of the explosion-proof isolation coal pillar can be judged to meet the safety requirement under the most unfavorable working condition, the explosion-proof isolation coal pillar can also meet the safety requirements under other working conditions.
In summary, the invention provides a house-column type overhead goaf explosion-proof isolation coal pillar width checking method, which is used for checking whether the width of an explosion-proof isolation coal pillar meets the safety requirement or not by determining the range and main mining parameters of the house-column type overhead goaf and effectively judging whether the width of the explosion-proof isolation coal pillar meets the shearing damage criterion and the bending damage criterion under the condition of unknown distribution of concrete coal houses and coal pillars. The method is a new checking method for judging whether the width of the explosion-proof isolation coal pillar of the room and column type overhead goaf can meet the safety requirement or not under the condition of unknown conditions, and can effectively prevent underground casualties, roadways and equipment damage caused by shock waves generated by sudden large-area collapse of the room and column type overhead goaf.
Finally, it should be noted that: the above embodiments are only for illustrating the technical aspects of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those of ordinary skill in the art that: modifications and equivalents may be made to the specific embodiments of the invention without departing from the spirit and scope of the invention, which is intended to be covered by the claims.

Claims (7)

1. The method for checking the width of the explosion-proof isolation coal pillar in the room-pillar overhead goaf is characterized by comprising the following steps of:
Step 1, determining the range and parameters of a room-pillar overhead goaf and the width of an explosion-proof isolation coal pillar, wherein the room-pillar overhead goaf parameters comprise the width of a coal room, the width of the coal pillar and the mining height;
And 2, setting that only one roadway is communicated between a room and pillar overhead goaf and an explosion-proof isolation coal pillar as the most unfavorable working condition, obtaining roadway parameters according to the room and pillar overhead goaf parameters, wherein the roadway parameters comprise the clear width and the clear height of the roadway, judging whether the width of the explosion-proof isolation coal pillar meets the safety requirement, and when the explosion wave formed after the room and pillar overhead goaf collapses breaks the explosion-proof isolation coal pillar, judging that the width of the explosion-proof isolation coal pillar does not meet the safety requirement, otherwise, judging that the width of the explosion-proof isolation coal pillar meets the safety requirement.
2. The method for checking the width of the explosion-proof isolation coal pillar in the room and pillar overhead goaf according to claim 1, wherein the room and pillar overhead goaf is in an overhead state, and the explosion-proof isolation coal pillar tightly wraps around the edge of the room and pillar overhead goaf to form a closed wall for isolating the room and pillar overhead goaf from the existing production system.
3. The room and pillar overhead goaf explosion-proof isolation coal pillar width checking method according to claim 2, wherein the stress of a closed wall formed by the explosion-proof isolation coal pillar is calculated according to the following formula:
Wherein P represents the air impact load applied to the tunnel sealing wall and MPa; k represents a loss coefficient of the wind flow velocity moving in the wind path, represents energy loss when wind flow reaches the closed wall from the goaf through a series of roadways, and is 0.1-0.5 according to the communication condition of the closed wall and the collapse area; a represents the caving area of the goaf roof, m 2; p represents the coal seam mining rate; ρ represents the air density, kg/m 3; g represents the acceleration of gravity, kg/m 3; m represents coal seam mining height/M; s represents the roadway cross-sectional area, m 2.
4. The room and pillar overhead goaf explosion-proof isolation coal pillar width checking method is characterized in that the method for judging the width safety requirement of the explosion-proof isolation coal pillar is to check the shearing damage criterion of the isolation coal pillar and check the bending damage criterion of the explosion-proof isolation coal pillar in sequence, and when the width colleagues of the explosion-proof isolation coal pillar meet the checking of the shearing damage criterion and the checking of the bending damage criterion, the width of the explosion-proof isolation coal pillar is judged to meet the safety requirement.
5. The room and pillar overhead goaf explosion-proof isolation coal pillar width checking method according to claim 4, wherein the calculation formula of the explosion-proof isolation coal pillar width shear failure criterion is as follows:
Wherein m represents the width of the sealing wall, and m; h represents the height of the sealing wall, m; d represents the thickness of the sealing wall, m; [ τ j ] represents the shear strength of the sealing wall, pa; p represents the air impact load applied to the tunnel sealing wall and MPa; s represents the roadway cross-sectional area, m 2.
6. The method for checking the width of the explosion-proof isolation coal pillar in the room-pillar overhead goaf according to claim 4, wherein the calculation formula of the bending failure criterion of the width of the explosion-proof isolation coal pillar is as follows:
Wherein lambda represents a coefficient, and the value is taken according to an internal force coefficient table of the four-side simple support plate under the action of uniformly distributed load and the length-width ratio of the combined plate; [ τ w ] represents the tensile strength of the sealing wall and Pa; d represents the thickness of the sealing wall, m; p represents the air impact load applied to the tunnel sealing wall and MPa; h represents the height of the sealing wall and m.
7. The method for checking the width of the explosion-proof isolation coal pillar of the room and pillar overhead goaf according to claim 1, wherein when the number of roadways between the room and pillar overhead goaf and the explosion-proof isolation coal pillar is larger, the smaller the impact of the impact wave formed after the room and pillar overhead goaf collapses on the explosion-proof isolation coal pillar is, and conversely the larger the impact of the impact wave formed after the room and pillar overhead goaf collapses on the explosion-proof isolation coal pillar is.
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CN106779231B (en) * 2016-12-28 2018-12-11 中国矿业大学 A kind of coal mine gob hurricane disaster method for early warning based on goaf pressure monitoring
CN108915764B (en) * 2018-07-09 2019-04-30 中国矿业大学 A method of reserved roadway cementation filling and recycling room-type coal pillars
CN110397470B (en) * 2019-07-15 2020-05-26 中国矿业大学 A method for determining the reasonable width of narrow coal pillars in gob-side entry based on crack evolution

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Publication number Priority date Publication date Assignee Title
CN113982686A (en) * 2021-09-10 2022-01-28 中煤科工开采研究院有限公司 Coal mining method and system for short-distance coal seam group hollow-chamber column type goaf
CN113987844A (en) * 2021-12-27 2022-01-28 华北科技学院(中国煤矿安全技术培训中心) House pillar type goaf stability dynamic evaluation method and system

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