Coal mine underground reservoir and construction method thereof

Abstract

The invention provides a coal mine underground reservoir and a construction method thereof, and relates to the technical field of coal mines. The coal mine underground reservoir comprises a reservoir dam body located on the peripheral side of a goaf after coal mining, and the reservoir dam body comprises a coal pillar dam body formed around the goaf; the top plate is positioned above the goaf; the bottom plate is located below the goaf, and a water storage area is defined by the reservoir dam body, the top plate and the bottom plate; the structure is arranged in the water storage area and comprises a dam foundation, a dam body and an anchor rod, the bottom of the dam foundation is connected with the bottom plate, the dam body is arranged at the top of the dam foundation, and the anchor rod penetrates through the dam foundation to be connected with the bottom plate and the dam body; the dam body is of a pyramid structure, the bottom face of the pyramid structure is connected with the dam foundation, and the vertex of the pyramid structure faces the top plate. Therefore, the dam body of the pyramid structure can relieve the impact effect of top plate overlying strata collapse on water, the shearing effect of water on the coal pillar dam body is relieved, and the stability and reliability of the coal pillar dam body can be improved.

Description

Technical Field

[0001] This application relates to the technical field of coal mines, and particularly to an underground coal mine reservoir and its construction method. Background Art

[0002] The "Golden Triangle" region of energy (Shanxi, Shaanxi, Inner Mongolia, Ningxia, and Gansu) is the main coal production area in China. However, the "Golden Triangle" of energy is located in arid and semi-arid climate regions, and water shortage has been a long-standing problem. For this reason, underground coal mine reservoirs are usually used to solve the water supply problem in water-scarce mining areas. Among them, the underground coal mine reservoir is a technology that uses the voids between the caving rock masses in the goaf of the coal mine to store mine water. Using the goaf underground in the coal mine as the space for storing, purifying, and recycling mine water can effectively protect and utilize mine water resources, is conducive to ecological restoration and green mining, and meets the requirements of green mining and sustainable development of coal mines in China. However, on the basis of the original rock stress, the coal pillar dam on the periphery of the goaf may also be subjected to the shear impact load from groundwater caused by the caving of the roof rock above the water storage area, which poses a great threat to the stability of the coal pillar dam. Summary of the Invention

[0003] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further described in detail in the Detailed Implementation section. This section of the present invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0004] An embodiment of the first aspect of this application provides an underground coal mine reservoir, including: a reservoir dam located on the periphery of the goaf after coal seam mining, and the reservoir dam includes a coal pillar dam formed around the goaf; a roof located above the goaf; a floor located below the goaf, and the reservoir dam, the roof, and the floor enclose a water storage area; a structure disposed in the water storage area, and the structure includes a dam foundation, a dam body, and anchor bolts. The bottom of the dam foundation is connected to the floor, the dam body is disposed on the top of the dam foundation, and the anchor bolts pass through the dam foundation to connect the floor and the dam body; wherein, the dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the vertex of the pyramid structure faces the roof.

[0005] Exemplarily, the dam foundation includes a housing and a non-Newtonian fluid filling material filled inside the housing. The housing and the dam body are formed by concrete pouring, and / or the number of anchor bolts is at least one.

[0006] Exemplarily, the non-Newtonian fluid filling material includes a shear thickening non-Newtonian fluid; and / or the housing is a rectangular box structure, and the dam body is a regular square pyramid structure.

[0007] Exemplarily, multiple structures are arranged in rows in the goaf, and two adjacent rows of structures are arranged staggeredly.

[0008] Exemplarily, the distance between two adjacent structures in the same row is 13 m to 17 m; the distance between two adjacent rows of structures is 18 m to 22 m; the structures in the same row are distributed at intervals transversely, and multiple rows of structures are distributed at intervals longitudinally, and the longitudinal direction is parallel to the advancing direction of the working face of coal seam mining.

[0009] Exemplarily, the vertex of the dam body is higher than the liquid level of the water storage area, and the height difference between the vertex of the dam body and the liquid level of the water storage area is greater than or equal to 0.2 m.

[0010] Exemplarily, the underground coal mine reservoir further includes: a liquid conveying device, which is communicated with the water storage area and is used for pumping or recharging the liquid in the water storage area; and / or, the reservoir dam body further includes an artificial dam body connecting the coal pillar dam body, and at least part of the artificial dam body is located on the side of the reservoir dam body adjacent to the working face.

[0011] Exemplarily, the underground coal mine reservoir further includes a plurality of stress detection devices and sandbags. The plurality of stress detection devices are arranged at intervals on the coal pillar dam body. The stress detection devices are used for detecting the stress of the coal pillar dam body at the relative position. The sandbags are arranged in the protection area of the coal pillar dam body, and the protection area includes the area of the coal pillar dam body corresponding to the stress detection device with abnormal detection value.

[0012] An embodiment of the second aspect of the present application provides a construction method of an underground coal mine reservoir for constructing the underground coal mine reservoir of any one of the foregoing embodiments. The construction method of the underground coal mine reservoir includes: performing a pretreatment operation on the goaf formed after coal seam mining; performing structure construction, wherein the step of performing structure construction includes: constructing the outer shell of the dam foundation in the goaf after the pretreatment operation, passing the first end of the anchor through the outer shell and fixing it to the bottom plate under the goaf, pouring a non-Newtonian fluid filling material into the outer shell, constructing the dam body, and fixing the second end of the anchor. The dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the vertex of the pyramid structure faces the roof above the goaf; performing a sandbag protection operation, wherein the step of performing a sandbag protection operation includes: arranging stress detection devices at different positions of the coal pillar dam body, and arranging sandbags in the area of the coal pillar dam body corresponding to the stress detection device with abnormal detection value.

[0013] Exemplarily, the construction method of the underground coal mine reservoir further includes: constructing an artificial dam body, at least part of the artificial dam body is located on the side of the reservoir dam body adjacent to the working face and is configured to be able to communicate two adjacent goafs; wherein, before the step of constructing the artificial dam body, it further includes: using the liquid conveying device to pump out the liquid in the goaf storing the liquid; and / or performing the steps of performing a pretreatment operation on the goaf formed after coal seam mining, performing structure construction, and performing a sandbag protection operation.

[0014] Exemplarily, the steps of preprocessing the gob area formed after coal seam mining include: cleaning the coal gangue within a preset distance from the coal pillar dam in the gob area, and the preset distance is 80m to 120m.

[0015] The underground coal mine reservoir and its construction method provided by the embodiments of the present application. The underground coal mine reservoir includes a reservoir dam body, a roof, a floor, and a structure. The structure is arranged in the water storage area. The bottom of the dam foundation of the structure is connected to the floor, the dam body is arranged on the top of the dam foundation, and anchor bolts are passed through the dam foundation. The two ends of the anchor bolts are respectively fixed on the floor and the dam body. By setting the dam body as a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the vertex of the pyramid structure faces the roof. An inclined side is connected between the vertex and the bottom surface of the dam body. In this way, when the rock (such as overlying rock) of the roof collapses, the vertex of the dam body has a supporting effect on the collapsed roof, and the inclined side arranged between the vertex and the bottom surface of the dam body has a supporting effect on the collapsed roof, so that the shear force can be more evenly distributed on the bottom surface, thereby reducing the phenomenon of local stress concentration. The inclined side provides good support and stability, further enhancing the shear resistance of the structure, and then being able to slow down the impact of the overlying rock collapse on the water and the shear effect of the water on the coal pillar dam body, which is beneficial to improving the reliability of the coal pillar dam body.

[0016] Furthermore, the dam body of the structure is a regular square pyramid structure. The tip of the regular square pyramid structure has a supporting effect on the collapsed roof. The shear thickening non-Newtonian fluid filled in the inner cavity of the dam foundation of the structure can further buffer the vertical impact caused by the roof collapse. The staggered arrangement of several structures can achieve the purpose of gradually slowing down the shear impact of groundwater. Through the above structure and the arrangement method of the structure, the shear impact load of groundwater on the coal pillar dam body caused by the roof collapse above the water storage area can be effectively slowed down. In addition, the present application sets a stress detection device at the coal pillar dam body to monitor the stress concentration area of the coal pillar dam body, and then strengthens the stress concentration area with sandbags. Through the above method, the stability of the coal pillar dam body of the underground coal mine reservoir can be effectively improved.

[0017] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention are specifically given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. And throughout the drawings, the same reference numerals are used to represent the same components. Among them: Figure 1 One of the schematic structural diagrams of an underground coal mine reservoir in the related art is shown; Figure 2 One of the schematic block diagrams of a partial structure of an underground coal mine reservoir provided by an embodiment of the present application is shown; Figure 3 One of the schematic structural diagrams of a structure provided by an embodiment of the present application is shown; Figure 4 One of the schematic block diagrams of a partial structure of an underground coal mine reservoir provided by an embodiment of the present application is shown; Figure 5 One of the schematic flow diagrams of a construction method of an underground coal mine reservoir provided by an embodiment of the present application is shown.

[0019] Among them, Figure 1 The corresponding relationship between the reference numerals and the component names in the figure is as follows: 100' underground coal mine reservoir, 111' coal pillar dam, 1111' first coal pillar dam, 1112' second coal pillar dam, 112' artificial dam, 120' roof, 140' water storage area, 160' gangue.

[0020] Among them, Figures 2 to 4 The corresponding relationship between the reference numerals and the component names in the figure is as follows: 100 underground coal mine reservoir, 101 goaf, 110 reservoir dam, 111 coal pillar dam, 1111 first coal pillar dam, 1112 second coal pillar dam, 112 artificial dam, 113 strike protection coal pillar, 120 roof, 130 structure, 131 dam foundation, 1311 outer shell, 1312 non-Newtonian fluid filling material, 1313 side wall, 1314 bottom wall, 1315 top wall, 132 dam body, 1321 bottom surface, 1322 apex, 133 anchor bolt, 140 water storage area, 150 floor. Detailed implementation manners

[0021] In order to be able to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0022] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0023] Such as Figure 1As shown, in the coal mine underground reservoir 100' in the related art, a coal pillar dam body 111' and an artificial dam body 112' are arranged on the peripheral side of the goaf after coal seam mining. There is gangue 160' in the goaf, and the goaf gangue 160' is used for water storage through its gaps. When using the coal mine underground reservoir 100' for water storage, if the overlying rock of the roof 120' above the water storage area 140' suddenly collapses, it will have a dynamic impact on the water. Through the transmission of water, a horizontal shear force will be applied to the coal pillar dam body 111' in the horizontal direction, seriously endangering the stability of the coal pillar dam body 111'.

[0024] For this reason, as Figure 2 and Figure 3 shown, an embodiment of the first aspect of the present application provides a coal mine underground reservoir 100, including: a reservoir dam body 110, located on the peripheral side of the goaf 101 after coal seam mining, and the reservoir dam body 110 includes a coal pillar dam body 111 formed around the goaf 101; a roof 120, located above the goaf 101; a floor 150, located below the goaf 101, and the reservoir dam body 110, the roof 120, and the floor 150 enclose a water storage area 140; a structure 130, arranged in the water storage area 140, and the structure 130 includes a dam foundation 131, a dam body 132, and an anchor rod 133. The bottom of the dam foundation 131 is connected to the floor 150, the dam body 132 is arranged on the top of the dam foundation 131, the first end of the anchor rod 133 passes through the inside of the dam foundation 131 and is connected to the floor 150, and the second end of the anchor rod 133 passes through the dam foundation 131 and is connected to the dam body 132; wherein, the dam body 132 is a pyramid structure, the bottom surface 1321 of the pyramid structure is connected to the dam foundation 131, and the vertex 1322 of the pyramid structure faces the roof 120.

[0025] The underground coal mine reservoir 100 provided by the embodiments of the present application includes a reservoir dam body 110, a roof 120, a floor 150, and a structure 130. Among them, the roof 120 is located above the goaf 101 and can be the coal seam roof 120. The floor 150 is located below the goaf 101 and can be the coal seam floor 150. The reservoir dam body 110, the roof 120, and the floor 150 enclose a water storage area 140 for storing groundwater. The structure 130 is arranged in the water storage area 140. The bottom of the dam foundation 131 of the structure 130 is connected to the floor 150, and the dam body 132 is arranged on the top of the dam foundation 131. Anchor rods 133 penetrate through the dam foundation 131, and both ends of the anchor rods 133 are fixed on the floor 150 and the dam body 132 respectively. By setting the dam body 132 as a pyramid structure, the bottom surface 1321 of the pyramid structure is connected to the dam foundation 131, and the vertex 1322 of the pyramid structure faces the roof 120. It can be understood that there are inclined side surfaces connected between the vertex 1322 and the bottom surface 1321 of the dam body 132. The bottom surface 1321 of the pyramid structure and the inclined side surfaces enable the dam body 132 to better distribute and resist shear forces when bearing shear forces, making the overall structure of the dam body 132 of the pyramid structure more stable, reducing the possibility of shear deformation, and having strong shear resistance. In this way, when the rocks (such as overlying rocks) of the roof 120 collapse, the vertex 1322 of the dam body 132 has a supporting effect on the collapsed roof 120, and the inclined side surfaces between the vertex 1322 and the bottom surface 1321 of the dam body 132 have a supporting effect on the collapsed roof 120, so that the shear forces can be more evenly distributed on the bottom surface 1321, thereby reducing the phenomenon of local stress concentration. The inclined side surfaces of the pyramid structure provide good support and stability, further enhancing the shear resistance of the dam body 132, and further being able to slow down the impact of the overlying rock collapse on the water. Therefore, by using the vertex 1322 of the dam body 132 of the pyramid structure and the inclined surfaces arranged obliquely, the impact of the rock collapse on the water in the water storage area 140 can be slowed down, and further the shear effect of the water on the coal pillar dam body 111 can be slowed down, which is beneficial to improving the stability and reliability of the coal pillar dam body 111 and the reliability of the underground coal mine reservoir 100.

[0026] Among them, the anchor rod 133 penetrates through the dam foundation 131, and both ends of the anchor rod 133 are respectively fixed on the bottom plate 150 and the dam body 132. The arrangement of the anchor rod 133 can reliably fix the structure 130 on the bottom plate 150, improve the reliability and stability of the connection between the structure 130 and the bottom plate 150, and can reduce the possibility that the collapsed rock damages and moves the dam body 132 and the entire structure 130, and improve the overall strength and reliability of the structure 130. Among them, the number of the anchor rods 133 can be one, two or more, and the number of the anchor rods 133 can be reasonably set according to the size and strength of the anchor rods 133 and the sizes of the dam foundation 131 and the dam body 132. It can be understood that the more the number of the anchor rods 133, the more reliable and stable the connection between the structure 130 and the bottom plate 150, and the higher the strength and reliability of the structure 130 itself.

[0027] Among them, there are multiple structures 130, and the multiple structures 130 are arranged at intervals in the goaf 101. In this way, the roof 120 in different areas collapses, and there will be a structure 130 to support the collapsed roof 120, so as to reduce the impact of the collapse of the roof 120 rock on the water in the underground coal mine reservoir 100, slow down the shearing effect of the water on the coal pillar dam body 111, and improve the reliability of the coal pillar dam body 111. At the same time, due to the impact force of the water in the horizontal direction, which is transmitted step by step from the collapse point of the rock collapse in the water to the distance, by setting multiple structures 130, the impact effect of the water in the horizontal direction can be gradually slowed down to further reduce the shearing effect of the water on the coal pillar dam body 111.

[0028] Specifically, multiple structures 130 can be set in the areas where the roof 120 is likely to collapse in the goaf 101, or multiple structures 130 can be set in the preset areas of the goaf 101. For example, the preset area can be the area range from 180 m to 120 m away from the coal pillar dam body 11 in the goaf 101. It can be understood that there is coal gangue in the goaf 101, and the gangue in the preset area can be cleaned up before constructing the structure 130 to lay a foundation for the construction of the structure 130.

[0029] Among them, as Figure 2 shown, the reservoir dam body 110 includes a coal pillar dam body 111, and the coal pillar dam body 111 can be formed by the periphery of the goaf 101. It can be understood that the reservoir dam body 110 can also include an artificial dam body 112, and the artificial dam body 112 is connected to the coal pillar dam body 111, and at least part of the artificial dam body 112 is located on the side of the reservoir dam body 110 adjacent to the working face.

[0030] As Figure 2As shown, specifically, the coal pillar dam body 111 may include a first coal pillar dam body 1111 and a second coal pillar dam body 1112. The first coal pillar dam body 1111 is the coal pillar adjacent to the working face, and the second coal pillar dam body 1112 is the coal pillar not adjacent to the working face. Among them, at least part of the artificial dam body 112 is located on the side of the reservoir dam body 110 adjacent to the working face. This part of the artificial dam body 112 can be connected to the first coal pillar dam body 1111. For example, at least part of the artificial dam body 112 can be arranged in the middle of the first coal pillar dam body 1111 to connect two adjacent parts of the first coal pillar dam body 1111. Or, at least part of the artificial dam body 112 can be arranged at the end of the first coal pillar dam body 1111 to connect the first coal pillar dam body 1111 and the second coal pillar dam body 1112. Specifically, at least part of the first coal pillar dam body 1111 is adjacent to the working face. In this way, when the goaf 101 is formed again after the working face, the first coal pillar dam body 1111 and the artificial dam body 112 on the side adjacent to the working face are located between two goafs 101. The artificial dam body 112 on the side adjacent to the working face is configured to be able to connect or isolate two adjacent goafs 101. In this way, structures 130 can be arranged in both adjacent goafs 101. By connecting the two goafs 101 through the artificial dam body 112 on the side adjacent to the working face, the range of the water storage area 140 can be increased and the water storage capacity can be expanded. And as Figure 1 shown, in the coal mine underground reservoir 100' in the related art, there is no artificial dam body 112' on the side adjacent to the working face. For example, the artificial dam body 112' is located on the side of the reservoir dam body not adjacent to the working face. For example, the artificial dam body 112' is located on the adjacent side of the first coal pillar dam body 1111' adjacent to the working face, and the artificial dam body 112' is connected to the second coal pillar dam body 1112' not adjacent to the working face, and it does not have the function of connecting two adjacent goafs. Therefore, in this application, by reasonably setting the position of part of the artificial dam body 112, at least part of the artificial dam body 112 is arranged adjacent to the working face and connected to the first coal pillar dam body 1111 adjacent to the working face, so that the artificial dam body 112 on the side adjacent to the working face can connect two adjacent goafs 101, so as to facilitate increasing the water storage space of the coal mine underground reservoir 100 and improving the water storage capacity.

[0031] Furthermore, as Figure 2As shown in the figure, the reservoir dam body 110 further includes a strike protection coal pillar 113 located inside the water storage area 140. The strike protection coal pillar 113 is located between two parts of the first coal pillar dam body 1111 adjacent to the working face side and extends along the advancing direction of the working face of the original coal seam mining, that is, the strike protection coal pillar 113 extends longitudinally to play a supporting role for the roof 120 in the water storage area 140. Among them, an artificial dam body 112 can also be arranged between the strike protection coal pillars 113, that is, part of the artificial dam body 112 extends longitudinally to connect two adjacent parts of the strike protection coal pillars 113. It can be understood that the artificial dam body 112 connecting the strike protection coal pillars 113 can connect or isolate the water storage areas on both sides of the strike protection coal pillars 113.

[0032] As Figure 3 shown, in some possible implementation embodiments provided by the present application, the dam foundation 131 includes a housing 1311 and a non-Newtonian fluid filling material 1312 filled inside the housing 1311. The housing 1311 and the dam body 132 are formed by concrete pouring.

[0033] Among them, the non-Newtonian fluid filling material 1312 filled inside the housing 1311 can reduce the vertical impact effect of the roof 120 rock collapse, thereby greatly slowing down the impact effect of the overlying rock collapse on the water, and further slowing down the shearing effect of the water on the coal pillar dam body 111, improving the reliability and stability of the coal pillar dam body 111.

[0034] Among them, non-Newtonian fluid refers to a fluid that does not satisfy Newton's viscosity experimental law, that is, a fluid whose shear stress and shear strain rate are not linearly related. Specifically, concentrated solutions and suspensions of high molecular polymers are generally non-Newtonian fluids. Such as polyethylene, polyacrylamide, polyvinyl chloride, nylon 6, PVS, celluloid, polyester, rubber solution, various engineering plastics, melts and solutions of chemical fibers, etc. are all non-Newtonian fluids. Petroleum, mud, coal water slurry, ceramic slurry, pulp, well washing fluid and completion fluid for drilling, magnetic slurry, high sediment-laden water flow, debris flow, mantle, etc. are also all non-Newtonian fluids.

[0035] Among them, the housing 1311 and the dam body 132 are formed by concrete pouring, which is convenient for construction, easy to implement, and is beneficial to improving the reliability of the entire structure 130.

[0036] In some possible implementation embodiments provided by the present application, the non-Newtonian fluid filling material 1312 includes shear thickening non-Newtonian fluid. For example, in actual production, shear thickening non-Newtonian fluid can be selected as shear thickening cement slurry. For example, carbon nanotubes or carbon nanotube / polyvinyl alcohol mixture are added to the cement slurry to make the cement slurry show obvious shear thickening effect when being impacted. Thus, the impact effect of the roof 120 rock collapse can be further reduced, thereby greatly slowing down the impact effect of the overlying rock collapse on the water.

[0037] As Figure 2 shown, in some possible embodiments provided by the present application, multiple structures 130 are arranged in rows in the goaf 101, and two adjacent rows of structures 130 are arranged staggeredly.

[0038] Due to the impact force of water in the horizontal direction, the collapse points where the rock collapses into the water are transmitted step by step to the distance. Through the staggered distribution form of multiple structures 130, the impact effect of water in the horizontal direction can be gradually reduced. That is to say, the impact effect of water farther away from the rock collapse point is weaker. Thus, the shear effect of water on the coal pillar dam body 111 can be reduced.

[0039] That is to say, for the underground coal mine reservoir 100 provided by the embodiments of the present application, by reasonably setting the shape of the structure 130, the material of the structure 130, and the arrangement mode of multiple structures 130, the shear impact effect of water caused by the collapse of the roof 120 rocks is reduced from the following three aspects. First, the dam body 132 of the structure 130 is a pyramid structure, and the vertex of the pyramid structure has a supporting effect on the collapsed roof 120. Second, by arranging non-Newtonian fluid materials inside the dam foundation 131 of the structure 130, the impact effect of the collapse of the roof 120 can be reduced, thereby greatly reducing the impact effect of the overlying rock collapse on the water, and further reducing the shear effect of the water on the coal pillar dam body 111. Third, multiple structures 130 are staggered, and the impact effect of water in the horizontal direction can be gradually reduced. The farther away from the collapse point, the weaker the impact effect of the water, so as to reduce the shear effect of the water on the coal pillar dam body 111.

[0040] As Figure 2 shown, in some possible embodiments provided by the present application, the distance between two adjacent structures 130 in the same row is 13 m to 17 m, and the distance between two adjacent rows of structures 130 is 18 m to 22 m. Among them, the distance between two adjacent structures 130 in the same row is as shown by D1 in Figure 2 , and the distance between two adjacent rows of structures 130 is as shown by D2 in Figure 2 . Specifically, the distance between two adjacent structures 130 in the same row can be 15 m, and the distance between two adjacent rows of structures 130 can be 20 m.

[0041] In this embodiment, by reasonably setting the spacing D1 between two adjacent structures 130 in the same row and the spacing D2 between two adjacent rows of structures 130, multiple structures 130 can be relatively evenly distributed in the area where the roof 120 is prone to caving. After the roof 120 at different positions caves in, it can be supported by the structures 130 at the corresponding positions, so as to play a good buffering role, slow down the impact of overlying strata caving on water, and further slow down the shearing action of water on the coal pillar dam body 111. At the same time, by reasonably setting the distance between two adjacent structures 130 in the same row and the distance between two adjacent rows of structures 130, the impact of water in the horizontal direction can be gradually slowed down, so as to further reduce the shearing action of water on the coal pillar dam body 111.

[0042] Specifically, the spacing D1 between two adjacent structures 130 in the same row is 13m, 14m, 15m, 16m, 17m, or other dimensions. The spacing D2 between two adjacent rows of structures 130 is 18m, 19m, 20m, 21m, 22m, or other dimensions.

[0043] In the above embodiment, the structures 130 in the same row extend horizontally, and multiple rows of structures 130 are spaced longitudinally. The longitudinal direction is parallel to the advancing direction of the working face of coal seam mining. That is to say, the advancing direction of the working face of the original coal seam corresponding to the goaf 101 is marked as the longitudinal direction, and the direction perpendicular to the advancing direction of the original working face is marked as the horizontal direction. As Figure 2 shown, the longitudinal direction is indicated by the arrow Y, and the horizontal direction is indicated by the arrow X. Several structures 130 are several rows spaced longitudinally. Each row has several structures 130 arranged at intervals horizontally. There is a certain horizontal dislocation distance between two adjacent rows of structures 130, so that two adjacent rows of structures 130 are arranged staggeredly.

[0044] As Figure 3 shown, in some possible embodiments provided by the present application, the outer shell 1311 of the dam foundation 131 is a rectangular box structure, and the dam body 132 is a regular square pyramid structure. Among them, the outer shell 1311 of the dam foundation 131 with a rectangular box structure and the dam body 132 with a regular square pyramid structure are convenient to process and easy to implement.

[0045] Among them, the dam body 132 with a regular square pyramid structure, due to the particularity of its geometric shape, such as the bottom surface 1321 of the regular square pyramid structure being a square and the side surfaces being isosceles triangles, this structure enables it to better distribute and resist shear force when bearing shear force. The square bottom surface 1321 and the isosceles triangle side surfaces make the overall structure more stable, reducing the possibility of shear deformation. Thus, the impact of overlying rock caving on water is mitigated. At the same time, since the projection of the vertex 1322 of the regular square pyramid structure on the bottom surface 1321 is the center of the bottom surface 1321, this means that when subjected to shear force, the shear force can be more evenly distributed on the bottom surface 1321, thereby reducing local stress concentration. In addition, the isosceles triangle side surfaces provide good support and stability, further enhancing the shear resistance of the structure, and thus being able to mitigate the impact of overlying rock caving on water.

[0046] As Figure 4 shown, in some possible implementation embodiments provided by the present application, the vertex 1322 of the dam body 132 is higher than the liquid level height of the water storage area 140, and the height difference between the vertex 1322 of the dam body 132 and the liquid level height of the water storage area 140 is greater than or equal to 0.2 m. So that the rocks caving from the roof 120, after being supported by the vertex 1322 of the dam body 132 and the inclined side surfaces of the dam body 132, fall into the liquid level of the water storage area 140. Thus, it is ensured that the dam body 132 of the structure 130 can reliably mitigate the impact of the roof 120 rock caving on water, and further mitigate the shear effect of water on the coal pillar dam body 111, which is beneficial to improving the stability and reliability of the coal pillar dam body 111 and enhancing the reliability of the underground coal mine reservoir 100. Among them, Figure 4 the dashed line L in represents the liquid level height of the water storage area 140, and the height difference between the vertex 1322 of the dam body 132 and the liquid level height L of the water storage area 140 is as Figure 4 shown by H in.

[0047] That is to say, the height of the dam body 132 of the structure 130 depends on the water volume of the water storage area 140. Specifically, the vertex 1322 of the dam body 132 should be 0.2 m or more higher than the liquid level height when the underground coal mine reservoir 100 stores water. Specifically, H can be 0.2 m, 0.25 m, 0.3 m, 0.35 m, or other dimensions. It can be understood that for the same liquid level height, the greater the height of H, the larger the volume of the structure 130, the more materials are used, and the higher the cost. Thus, by reasonably setting the height difference between the vertex 1322 of the dam body 132 and the liquid level height of the water storage area 140 to be 0.2 m, on the basis of ensuring that the dam body 132 of the structure 130 has good shear resistance and can reliably mitigate the impact of overlying rock caving on water, the volume of the structure 130 is greatly reduced and the cost is saved.

[0048] In some possible embodiments provided by the present application, the underground coal mine reservoir 100 further includes: a liquid conveying device, which is communicated with the water storage area 140 and is used for pumping or recharging the liquid in the water storage area 140.

[0049] Through the arrangement of the liquid conveying device, water in other areas can be conveyed to the water storage area 140 of the underground coal mine reservoir 100 for storage, and the stored water in the underground coal mine reservoir 100 can also be conveyed to other positions. Thus, the pumping or recharging of the liquid in the water storage area 140 is realized, so as to realize water supply or water level regulation, facilitating the conveyance of water in the underground coal mine reservoir 100.

[0050] In some possible embodiments provided by the present application, the underground coal mine reservoir 100 further includes a plurality of stress detection devices and sandbags. The plurality of stress detection devices are arranged at intervals on the coal pillar dam body 111. The stress detection devices are used for detecting the stress of the coal pillar dam body 111 at the relative position. The sandbags are arranged in the protection area of the coal pillar dam body 111, and the protection area at least includes the area of the coal pillar dam body 111 corresponding to the stress detection device with an abnormal detection value.

[0051] Among them, if the detection value of the stress detection device is abnormal, it indicates that the stress of the coal pillar dam body 111 at the relative position is concentrated, that is, the stress detection device can determine the stress concentration area of the coal pillar dam body 111, and then the sandbags are arranged in the stress concentration area of the coal pillar dam body 111 to play a role in strengthening the coal pillar dam body 111, thereby being able to assist in improving the reliability of the coal pillar dam body 111 and the reliability of the underground coal mine reservoir 100.

[0052] As Figure 5 shown, an embodiment of the second aspect of the present application provides a construction method for an underground coal mine reservoir 100, which is used for constructing the underground coal mine reservoir 100 in any of the foregoing embodiments, and includes the following method steps.

[0053] Step 501: Perform a pretreatment operation on the goaf formed after coal seam mining.

[0054] Among them, by performing a pretreatment operation on the goaf 101 formed after coal seam mining, a construction site is provided for the construction of the structure 130, laying a foundation for the construction of the structure 130.

[0055] Step 502: Perform the construction of the structure. Among them, the steps of performing the construction of the structure include: constructing the outer shell of the dam foundation in the goaf after the pretreatment operation, passing the first end of the anchor through the outer shell and fixing it to the bottom plate under the goaf, pouring a non-Newtonian fluid filling material into the outer shell, constructing the dam body, and fixing the second end of the anchor. The dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the vertex of the pyramid structure faces the roof above the goaf.

[0056] Among them, by pouring concrete into the outer shell 1311 of the dam foundation 131 and the dam body 132, it is beneficial to improve the strength of the structure 130. The first end of the anchor rod 133 passes through the inner part of the outer shell 1311 of the dam foundation 131 and is fixed to the rock of the bottom plate 150 through the dam foundation 131, and the second end of the anchor rod 133 is fixed to the dam body 132. Thus, the structure 130 can be reliably fixed on the bottom plate 150, and the overall strength and reliability of the structure 130 can be improved. By filling the non-Newtonian fluid filling material 1312 inside the outer shell 1311 of the dam foundation 131, the impact effect of the roof 120 rock collapse can be reduced, thereby greatly slowing down the impact effect of the overlying rock collapse on the water, and further slowing down the shear effect of the water on the coal pillar dam body 111.

[0057] By setting the dam body 132 as a pyramid structure, the bottom surface 1321 of the pyramid structure is connected to the dam foundation 131, and the vertex 1322 of the pyramid structure faces the roof 120. It can be understood that there are inclined side surfaces connected between the vertex 1322 and the bottom surface 1321 of the dam body 132. The bottom surface 1321 and the inclined side surfaces of the pyramid structure enable it to better distribute and resist shear force when bearing shear force, making the overall structure of the dam body 132 of the pyramid structure more stable, reducing the possibility of shear deformation, and having strong shear resistance. In this way, when the rock (such as overlying rock) of the roof 120 collapses, the vertex 1322 of the dam body 132 has a supporting effect on the collapsed roof 120, and the inclined side surfaces between the vertex 1322 and the bottom surface 1321 of the dam body 132 have a supporting effect on the collapsed roof 120, so that the shear force can be more evenly distributed on the bottom surface 1321, thereby reducing the phenomenon of local stress concentration, and the inclined side surfaces provide good support and stability, further enhancing the shear resistance of the structure, and further being able to slow down the impact effect of the overlying rock collapse on the water. Thus, by using the vertex 1322 of the dam body 132 and the inclined surfaces arranged obliquely, the impact effect of the rock collapse on the water in the water storage area 140 can be slowed down, and further the shear effect of the water on the coal pillar dam body 111 can be slowed down, which is beneficial to improving the reliability of the coal pillar dam body 111 and the reliability of the underground coal mine reservoir 100.

[0058] Step 503: Perform sandbag protection operation. Among them, the steps of performing the sandbag protection operation include: arranging stress detection devices at different positions of the coal pillar dam body, and arranging sandbags in the area of the coal pillar dam body corresponding to the stress detection device with abnormal detection values.

[0059] Among them, if the detection value of the stress detection device is abnormal, it indicates that the stress of the coal pillar dam body 111 at the corresponding position is concentrated, that is, the stress detection device can determine the stress concentration area of the coal pillar dam body 111, and then arrange sandbags in the stress concentration area of the coal pillar dam body 111 to play a role in strengthening the coal pillar dam body 111, and further be able to assist in improving the reliability of the coal pillar dam body 111 and the reliability of the underground coal mine reservoir 100.

[0060] In some possible embodiments provided by the present application, after the preprocessing operation, construct the outer shell of the dam foundation in the goaf, pass the first end of the anchor rod through the outer shell and fix it to the bottom plate below the goaf, pour non-Newtonian fluid filling material into the outer shell, construct the dam body, and fix the second end of the anchor rod. The dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the vertex of the pyramid structure faces the roof above the goaf. The specific steps include: After the preprocessing operation, use concrete to pour the side wall 1313 of the outer shell 1311 of the dam foundation 131 in the goaf 101, drive several anchor rods 133 into the bottom plate 150 rock formation, so that the shear-resistant structure 130 can be fixed. The height of the anchor rods 133 needs to be higher than the height of the dam foundation 131 for connection with the dam body 132. The anchor rods 133 are accommodated in the space surrounded by the side wall 1313; construct the bottom wall 1314 of the outer shell 1311 of the dam foundation 131 to prevent the non-Newtonian fluid with a buffering effect from seeping into the bottom plate 150 rock formation. Pour the non-Newtonian fluid filling material 1312 into the inner cavity of the outer shell 1311 of the dam foundation 131; construct the top wall 1315 of the outer shell 1311 of the dam foundation 131, and construct the dam body 132 on the top wall 1315 of the outer shell 1311 of the dam foundation 131, such as pouring the dam body 132 with concrete on the top wall 1315 of the outer shell 1311 of the dam foundation 131. Thus, the construction of the structure 130 is realized.

[0061] It can be understood that through step 502, the construction of multiple structures 130 can be carried out. The multiple structures 130 are arranged in rows at intervals in the goaf 101, and two adjacent rows of structures 130 are arranged staggeredly.

[0062] In some possible embodiments provided by the present application, the construction method of the underground coal mine reservoir further includes: constructing an artificial dam body, which is located on the side of the reservoir dam body adjacent to the working face and is configured to communicate with two adjacent goafs; wherein, before the step of constructing the artificial dam body, it further includes: using a liquid conveying device to pump out the liquid in the goaf storing the liquid; and / or performing preprocessing operations on the goaf formed after coal seam mining, performing structure construction, and performing sandbag protection operations.

[0063] In this embodiment, by constructing the artificial dam body 112, the adjacent goafs 101 are connected by the artificial dam body 112, thereby expanding the water storage space of the underground reservoir and increasing the water storage capacity. Specifically, the artificial dam body 112 is located on the side of the reservoir dam body 110 adjacent to the working face, that is, the artificial dam body 112 is connected to the first coal pillar dam body 1111 mentioned above. The two goafs 101 can be understood as the goafs 101 with structures 130 constructed therein, that is, the goafs 101 corresponding to the underground coal mine reservoir 100, and the adjacent goafs 101 without structures 130 constructed therein. The goafs 101 without structures 130 constructed therein can be understood as the goafs 101 formed by subsequent coal mining, and this goaf 101 is adjacent to the working face. Through the artificial dam body 112, the goaf 101 with structures 130 constructed therein can be connected to the goaf 101 of the adjacent working face without structures 130 constructed therein.

[0064] Specifically, if the adjacent working face is mined out and a new goaf 101 without structures 130 constructed therein is formed, at this time, the water in the underground coal mine reservoir 100 with structures 130 constructed therein can be temporarily pumped away and transferred by using a liquid conveying device. After all the water in the underground coal mine reservoir 100 is transferred, an artificial dam body 112 can be set on the side of the underground coal mine reservoir 100 adjacent to the working face. The artificial dam body 112 is used to connect the underground coal mine reservoir 100 with the goaf 101 of the adjacent working face without structures 130 constructed therein, and a pretreatment operation is carried out on the goaf 101 of the adjacent working face, the structure 130 is constructed, and a sandbag protection operation is carried out, that is, steps 501, 502, and 503 are repeated. Then, by using the liquid conveying device to convey the water to the water storage area 140, water storage can be realized. It can be understood that in this case, the range of the underground coal mine reservoir 100 is the water storage areas 140 of the two goafs 101, thereby expanding the water storage space of the underground reservoir and increasing the water storage capacity.

[0065] It can be understood that the steps of carrying out a pretreatment operation, constructing the structure 130, and carrying out a sandbag protection operation on the goaf 101 without structures 130 constructed after coal seam mining can also be carried out before the step of setting the artificial dam body 112 between the coal pillar dams 111, that is, after the steps of carrying out a pretreatment operation, constructing the structure 130, and carrying out a sandbag protection operation on the goaf 101 without structures 130 constructed, and then the step of constructing the artificial dam body 112 is carried out to connect the two goafs 101.

[0066] In some possible implementation embodiments provided by the present application, the step of carrying out a pretreatment operation on the goaf formed after coal seam mining includes: cleaning the coal gangue at a preset distance from the coal pillar dam 111 in the goaf, and the preset distance is 80 m to 120 m.

[0067] That is to say, before the construction of the structure 130, the gangue within the range of 80 m to 120 m from the goaf 101 to the coal pillar dam body 111 is cleared, laying a foundation for the construction of the shear-resistant structure 130. It can be understood that if there are problems such as a short caving distance of the roof 120 of the goaf 101 or construction difficulties, the range of gangue clearance can be appropriately changed.

[0068] In the description of the present invention, the term "a plurality of" refers to two or more, unless otherwise clearly defined. The orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention; terms such as "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0069] In the description of the present invention, the description of terms such as "an embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In the present invention, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A coal mine underground reservoir, characterized in that: include: The reservoir dam body is located on the periphery of the goaf area after coal seam mining, and the reservoir dam body includes a coal pillar dam body formed around the goaf area; A roof, located above the goaf; A bottom plate is located below the goaf, and the reservoir dam body, the top plate and the bottom plate together form a water storage area; A structure is arranged in the water storage area, the structure comprises a dam foundation, a dam body and an anchor rod, the bottom of the dam foundation is connected to the bottom plate, the dam body is arranged on the top of the dam foundation, and the anchor rod is passed through the dam foundation to connect the bottom plate and the dam body; The dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the apex of the pyramid structure faces the top plate.

2. The coal mine underground water reservoir according to claim 1, characterized in that: The dam foundation comprises an outer shell and a non-Newtonian fluid filling material filled in the outer shell, the outer shell and the dam body are cast by concrete, and / or, The number of the anchor rod is at least one.

3. The coal mine underground water reservoir according to claim 2, characterized in that: The non-Newtonian fluid filling material comprises a shear thickening non-Newtonian fluid; and / or, The shell is a rectangular box structure, and the dam body is a regular quadrangular pyramid structure.

4. The coal mine underground water reservoir according to claim 1, characterized in that: A plurality of the structures are arranged in rows in the goaf, and the structures in two adjacent rows are arranged in a staggered manner.

5. The coal mine underground water reservoir according to claim 4, characterized in that: The distance between two adjacent structures in the same row is 13m to 17m; The distance between two adjacent rows of the structures is 18m to 22m; The structures in the same row are distributed at intervals in the horizontal direction, and multiple rows of the structures are distributed at intervals in the vertical direction, and the vertical direction is parallel to the advancing direction of the working face of coal seam mining.

6. The coal mine underground water reservoir according to claim 1, characterized in that: The top of the dam body is higher than the liquid level of the water storage area, and the height difference between the top of the dam body and the liquid level of the water storage area is greater than or equal to 0.2m.

7. The coal mine underground water reservoir according to claim 1, characterized in that: Also includes: A liquid conveying device, the liquid conveying device is connected to the water storage area and is used to extract or refill the liquid in the water storage area; and / or, The reservoir dam body also includes an artificial dam body connected to the coal pillar dam body, and at least part of the artificial dam body is located on a side of the reservoir dam body adjacent to the working face.

8. The coal mine underground water reservoir according to claim 1, characterized in that: The coal mine underground water reservoir also includes a plurality of stress detection devices and sandbags. The plurality of stress detection devices are arranged at intervals on the coal pillar dam. The stress detection devices are used to detect the stress of the coal pillar dam at relative positions. The sandbags are arranged in a protection area of ​​the coal pillar dam. The protection area includes the area of ​​the coal pillar dam corresponding to the stress detection device with abnormal detection values.

9. A method for constructing an underground water reservoir in a coal mine, characterized in that: Used to construct a coal mine underground water reservoir as described in any one of claims 1 to 8, the construction method of the coal mine underground water reservoir comprises: Carry out pre-treatment operations on the goaf formed after coal seam mining; Carry out structure construction, wherein the steps of carrying out structure construction include: constructing a shell of a dam foundation in the goaf after the pretreatment operation, passing the first end of an anchor rod through the shell and fixing it to the bottom plate below the goaf, pouring non-Newtonian fluid filling material into the shell, constructing a dam body, and fixing the second end of the anchor rod, wherein the dam body is a pyramid structure, the bottom surface of the pyramid structure is connected to the dam foundation, and the apex of the pyramid structure faces the top plate above the goaf; Perform sandbag protection operations, wherein the steps of performing sandbag protection operations include: deploying stress detection devices at different positions of the coal pillar dam body, and arranging the sandbags in the area of ​​the coal pillar dam body corresponding to the stress detection device with abnormal detection values.

10. The construction method of the coal mine underground reservoir according to claim 9, characterized in that: Also includes: constructing an artificial dam body, wherein at least a part of the artificial dam body is located on a side of the reservoir dam body adjacent to the working surface and is configured to connect two adjacent goaf areas; Wherein, before the step of constructing the artificial dam body, the method further includes: Using a liquid conveying device to extract the liquid in the goaf where the liquid is stored; and / or The steps of performing the pretreatment operation, the structure construction and the sandbag protection operation on the goaf formed after coal seam mining.

Images