Arrangement method for mining working face of steeply inclined coal seam

Abstract

The invention discloses a steeply inclined coal seam mining working face arrangement method. The method comprises the steps that a target coal seam mining working face is sequentially divided into a horizontal section, an arc section and a pseudo-inclined section in the coal seam advancing direction; according to a preset target reduction angle of the working face inclination angle, in combination with coal seam parameters of the target coal seam and support parameters of the hydraulic support, a pseudo-dip angle enabling the working face inclination angle to meet the target reduction angle after pseudo-dip arrangement is carried out on the working face is calculated and determined; the lengths of the horizontal section, the arc section and the pseudo-inclined section correspond to the number of the required hydraulic supports; and arranging the working surfaces according to a calculation result to form a pseudo-inclined working surface consisting of a horizontal section working surface, an arc section working surface and a pseudo-inclined section working surface. Therefore, the mining efficiency of the bottom coal seam can be improved while the inclination angle of the mining working face is reduced.

Description

Technical Field

[0001] The present application relates to the field of mine technology, and in particular to a method for arranging a steeply inclined coal seam mining working face. Background Art

[0002] Steeply inclined coal seams refer to coal seams with an inclination angle greater than 45°. Due to the complex geological structure and difficulty in mining, such coal seams are generally considered complex and difficult to mine. With coal resources becoming increasingly scarce today, how to mine such coal seams efficiently and safely is of great significance to improving the utilization rate of coal resources and ensuring national energy security. Coal seams with a thickness greater than 3.5m are defined as thick coal seams, while those greater than 8m are considered extra-thick coal seams. In current coal mining technology, there is a large gap in mining technology for coal seams with a thickness of 5-17m. Coal seams in this thickness range neither fall within the scope of conventional thick coal seam mining nor are they fully included in the mining technology system for extra-thick coal seams. Therefore, their mining difficulty is particularly prominent.

[0003] When faced with such steeply inclined and thick coal seams, traditional mining methods often have problems such as low mining efficiency, poor safety, and low resource recovery rate. For example, although the horizontal layered mining method can reduce the mining inclination, the working face needs to be adjusted frequently during the layered mining process, resulting in low mining efficiency; while the top coal caving mining method may make it difficult to release the bottom coal body due to the large inclination of the coal seam, resulting in a low coal caving rate. At the same time, the working face has poor stability and great safety hazards. Therefore, there is an urgent need for a method for arranging the working face for steeply inclined thick and extra-thick coal seams to promote the safe and efficient mining of steeply inclined thick and extra-thick coal seams. Summary of the invention

[0004] The embodiment of the present application provides a method for arranging a mining working face in a steeply inclined coal seam, which can improve the mining efficiency of the bottom coal seam while reducing the inclination of the mining working face.

[0005] In order to achieve the above object, the technical solution of the embodiment of the present invention is:

[0006] In the first aspect, an embodiment of the present invention provides a method for arranging a steeply inclined coal seam mining working face, comprising: dividing the target coal seam mining working face into horizontal sections, arc sections and pseudo-inclined sections in sequence along the coal seam advancement direction; according to a preset target reduction angle of the working face inclination, combined with the coal seam parameters of the target coal seam and the support parameters of the hydraulic support, calculating and determining the pseudo-inclined angle after the working face is arranged in a pseudo-inclined manner so that the working face inclination meets the target reduction angle, as well as the lengths of the horizontal sections, arc sections and pseudo-inclined sections and the corresponding required number of hydraulic supports; wherein the coal seam parameters of the target coal seam include at least the coal seam inclination, the coal seam thickness and the working face inclination length; the hydraulic support parameters include the support center distance of the hydraulic support and the maximum support height of the hydraulic support; the working face is arranged according to the calculation results to form a pseudo-inclined working face composed of a horizontal section working face, an arc section working face and a pseudo-inclined section working face.

[0007] In some possible implementations, the horizontal section is located at the bottom of the working face to optimize the discharge efficiency of the coal body at the bottom of the working face; the length of the horizontal section is determined according to the target coal seam thickness and the horizontal width of the arc section; the length of the horizontal section is expressed as:

[0008] L1=H / sinα-L C ,

[0009] Among them, L1 is the length of the horizontal section, H is the target coal seam thickness, α is the target coal seam inclination, L C It is the width of the arc segment along the horizontal direction.

[0010] In some possible implementations, the arc segment is a transition segment from the horizontal segment to the pseudo-inclined segment, and the inclination angle is adjusted by the transition of a preset number of hydraulic supports; the length of the arc segment is determined according to the arc radius of the arc segment, the height of the hydraulic support, and the inclination angle of the coal seam; the length of the arc segment is expressed as:

[0011]

[0012] Among them, L2 is the length of the arc segment, R is the radius of the arc segment, and H s is the height of the hydraulic support, the radius of the arc segment R is calculated based on the arc length formula and the arc length L at the top beam of the hydraulic support H Determine that the arc segment radius R is expressed as:

[0013]

[0014] Where L H＝ N2*L S , N2 is the number of circular arc hydraulic supports, L S is the center distance of the hydraulic support, and the width L of the arc segment along the horizontal direction C =sinα*R.

[0015] In some possible implementations, the pseudo-inclined section adopts a pseudo-inclined working surface arrangement method to reduce the inclination angle of the working surface; the length of the pseudo-inclined section is determined according to the inclination projection length of the working surface, the length of the horizontal section and the length of the arc section; the length of the pseudo-inclined section is expressed as:

[0016] L3=L w -L1-L2,

[0017] Among them, L3 is the length of the pseudo-slope segment, L w L is the inclined projection length of the working surface, w It is expressed as:

[0018] L w =L1+L2+L3=N*L S ,

[0019] Wherein, N is the total number of hydraulic supports on the working face.

[0020] In some possible implementations, the number of hydraulic supports required for the horizontal segment, the arc segment, and the pseudo-inclined segment is determined according to the determined lengths of each segment and the center distance of the hydraulic supports.

[0021] In some possible implementations, the pseudo pitch angle is determined according to the actual length of the working surface and the projection length of the entire pseudo pitch working surface in the horizontal direction; the pseudo pitch angle is expressed as:

[0022]

[0023] Where β is the pseudo pitch angle, L Q is the actual length of the pseudo-inclined working surface, L X is the projection length of the pseudo-inclined working surface as a whole in the horizontal direction;

[0024] The actual length of the pseudo-inclined working surface is expressed as:

[0025]

[0026] Among them, α1 is the target reduction angle of the preset working surface inclination;

[0027] The overall projection length of the pseudo-inclined working surface in the horizontal direction is expressed as:

[0028]

[0029] In some possible implementations, the target coal seam is a steeply inclined coal seam with a mining inclination angle greater than 45°, and the thickness of the coal seam is greater than 5 m and less than 17 m.

[0030] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0031] In the embodiment of the present invention, the target coal seam mining working face is divided into a horizontal section, an arc section and a pseudo-inclined section in sequence along the coal seam advancement direction, wherein the horizontal section can release the bottom coal body better, solving the problem that the bottom coal body is usually difficult to release and the coal release rate is low when caving top coal in a coal seam with a steep inclination angle, and the sharp corner part of the original triangular area at the lower end of the working face is alleviated, which can effectively avoid the problem of stress concentration there, making the mining of steeply inclined or steeply inclined coal seams safer; the arc section is a transition section from the horizontal section to the pseudo-inclined section; the pseudo-inclined section can adopt the arrangement method of the pseudo-inclined working face, which can effectively reduce the inclination angle of the mining working face. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention, the accompanying drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0033] Figure 1 A schematic flow chart of an embodiment of a method for arranging a steeply inclined coal seam mining working face provided for the implementation of the present invention;

[0034] Figure 2 It is a structural schematic diagram of the working surface arrangement in an embodiment of the present invention;

[0035] Figure 3 A front view of the working surface arrangement in an embodiment of the present invention;

[0036] Figure 4 A left view of the working surface arrangement in an embodiment of the present invention;

[0037] Figure 5 A schematic diagram of the arrangement of arc segments of the working surface in an embodiment of the present invention;

[0038] Figure 6 It is a schematic diagram of the inclined working surface in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] In the relevant description of this embodiment, the terms "including, containing, having" and the like are open terms and are generally understood to include but not be limited to; the term "at least one" is generally understood to mean one or more, where "plurality" refers to two or more; the term "at least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items, for example, "at least one of a, b or c", or "at least one of a, b and c", can all represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively; the symbol "A / B" is used to describe the selection relationship of associated objects, generally indicating an "or" relationship before and after.

[0041] In the following description of the present embodiment, the terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0042] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of serial numbers does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0043] Those skilled in the art will appreciate that the numerical ranges in the embodiments of the present application are to be construed as also specifically disclosing each intermediate value between the upper and lower limits of the scope. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded in the scope.

[0044] Unless otherwise specified, the technical / scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which this application belongs. Although this application only describes preferred methods and materials, any methods and materials similar or equivalent to these may also be used in the implementation or testing of this application. All documents mentioned in this specification are incorporated by reference to disclose and describe methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0045] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for illustration.

[0046] Steeply inclined coal seams refer to coal seams with an inclination angle greater than 45°. Due to the complex geological structure and difficulty in mining, such coal seams are generally considered complex and difficult to mine. With coal resources becoming increasingly scarce today, how to mine such coal seams efficiently and safely is of great significance to improving the utilization rate of coal resources and ensuring national energy security. Coal seams with a thickness greater than 3.5m are defined as thick coal seams, while those greater than 8m are considered extra-thick coal seams. In current coal mining technology, there is a large gap in mining technology for coal seams with a thickness of 5-17m. Coal seams in this thickness range neither fall within the scope of conventional thick coal seam mining nor are they fully included in the mining technology system for extra-thick coal seams. Therefore, their mining difficulty is particularly prominent.

[0047] Traditional mining methods often have problems such as low mining efficiency, poor safety, and low resource recovery rate when facing such steeply inclined and thick coal seams. For example, although the horizontal layered mining method can reduce the mining inclination, the working face needs to be adjusted frequently during the layered mining process, resulting in low mining efficiency; while the top coal caving mining method may make it difficult to caving the bottom coal body due to the large inclination of the coal seam, resulting in a low caving rate, poor working face stability, and great safety hazards.

[0048] However, there are few methods for arranging mining faces for coal seams with a thickness of 5-17m. Therefore, there is an urgent need for a method for arranging mining faces for steeply inclined thick and extra-thick coal seams to promote safe and efficient mining of steeply inclined thick and extra-thick coal seams.

[0049] Based on this, an embodiment of the present invention provides a method for arranging a steeply inclined coal seam mining working face, which can improve the mining efficiency of the bottom coal seam while reducing the inclination angle of the mining working face.

[0050] Figure 1 A schematic diagram of an embodiment of a method for arranging a steeply inclined coal seam mining working face provided for the implementation of the present invention is shown in FIG. Figure 1 As shown, the above-mentioned steeply inclined coal seam mining working face arrangement method may include:

[0051] S101, dividing the target coal seam mining working face into horizontal segments, arc segments and pseudo-inclined segments along the coal seam advancing direction;

[0052] Among them, the horizontal section is located at the bottom of the working face, which is used to optimize the discharge efficiency of the coal body at the bottom of the working face; the arc section is the transition section from the horizontal section to the pseudo-inclined section, and the inclination angle is adjusted through the transition of a preset number of hydraulic supports; the pseudo-inclined section adopts the arrangement method of the pseudo-inclined working face to reduce the inclination angle of the working face;

[0053] Understandably, in steeply inclined coal seams, due to the large inclination of the coal seams, the bottom coal is often difficult to release smoothly, resulting in low coal resource recovery rate and even potential safety hazards. The setting of the horizontal section reduces the inclination of the bottom of the working face, making it easier for the coal to slide to the coal discharge port under the action of gravity, thereby improving the coal release efficiency and resource recovery rate. At the same time, the horizontal section also helps to enhance the stability of the working face and reduce the risk of coal seam collapse.

[0054] The arc section, as the transition section from the horizontal section to the pseudo-inclined section, plays a key role in connecting the upper and lower sections. The arc section is adjusted in inclination by a preset number of hydraulic supports to ensure a smooth transition of the working face from the horizontal section to the pseudo-inclined section. The setting of the arc section not only optimizes the geometric shape of the working face, but also achieves precise control of the inclination of the working face through the flexible adjustment of the hydraulic supports. This transition design helps to reduce stress concentration during the mining process, improve the overall stability of the working face, and at the same time reduce the additional load on the hydraulic supports, extending the service life of the equipment.

[0055] A pseudo-inclined working face refers to a certain angle between the working face and the direction of the coal seam. This arrangement method aims to reduce the inclination of the working face, thereby reducing the resistance in the mining process and improving the mining efficiency. First, by adjusting the angle between the working face and the direction of the coal seam, the true inclination of the working face can be effectively reduced. In this way, the resistance in the mining process is directly reduced, thereby improving the mining efficiency. Secondly, the setting of the pseudo-inclined section also ensures that the true inclination of the working face is greater than the minimum natural repose angle of the gangue. It not only reduces the risk of dynamic disasters such as flying gangue in the working face, but also ensures that the mined coal body can slide down smoothly in the predetermined direction, effectively reducing the occurrence of coal body jamming. In addition, the pseudo-inclined working face also helps to improve the ventilation conditions of the working face. By optimizing the layout of the working face, the dust concentration and harmful gas concentration in the working environment are reduced, thereby improving the safety and efficiency of the operation.

[0056] In some embodiments, the target coal seam is a steeply inclined coal seam with a mining inclination angle greater than 45°, and the thickness of the coal seam is between a thick coal seam of more than 5 m and an extra thick coal seam of less than 17 m.

[0057] S102, according to the preset target lowering angle of the working face inclination, combined with the coal seam parameters of the target coal seam and the support parameters of the hydraulic support, calculate and determine the pseudo pitch angle after the working face is arranged in a pseudo pitch so that the working face inclination meets the target lowering angle, as well as the lengths of the horizontal section, the arc section and the pseudo pitch section and the corresponding required number of hydraulic supports;

[0058] The coal seam parameters of the target coal seam at least include the coal seam inclination angle, coal seam thickness, and working face inclination length; the hydraulic support parameters include the support center distance of the hydraulic support and the maximum support height of the hydraulic support;

[0059] It should be noted that the coal seam inclination refers to the angle between the coal seam and the horizontal plane, which determines the sliding force of the coal body's own weight and the difficulty of mining during the mining process. The coal seam thickness refers to the vertical thickness of the coal seam, which affects the selection of mining equipment and mining efficiency. The working face inclination length refers to the length of the working face along the coal seam inclination direction, which determines the spatial scope and operating efficiency of the mining operation. The hydraulic support center distance refers to the distance between the centers of two adjacent hydraulic supports, which determines the layout density and support effect of the supports. The maximum support height of the hydraulic support refers to the maximum support height that the hydraulic support can provide, which determines the applicability of the support under different coal seam thicknesses.

[0060] In some embodiments, the horizontal section is located at the bottom of the working face, and is used to optimize the discharge efficiency of the coal body at the bottom of the working face; the length of the horizontal section can be determined according to the target coal seam thickness and the horizontal width of the arc section;

[0061] Exemplarily, the horizontal segment length can be expressed as:

[0062] L1=H / sinα-L C ,

[0063] Among them, L1 is the length of the horizontal section, H is the target coal seam thickness, α is the target coal seam inclination, L C It is the width of the arc segment along the horizontal direction.

[0064] In some embodiments, the length of the arc segment can be determined according to the arc radius of the arc segment, the height of the hydraulic support and the inclination of the coal seam;

[0065] For example, the length of the arc segment can be expressed as:

[0066]

[0067] Among them, L2 is the length of the arc segment, R is the radius of the arc segment, and H s is the height of the hydraulic support, the radius of the arc segment R is calculated based on the arc length formula and the arc length L at the top beam of the hydraulic support H Determine that the arc segment radius R is expressed as:

[0068]

[0069] Among them, L H＝ N2*L S , N2 is the number of circular arc hydraulic supports, L S is the center distance of the hydraulic support, and the width L of the arc segment along the horizontal direction C =sinα*R.

[0070] In some embodiments, the pseudo-inclined section adopts a pseudo-inclined working surface arrangement method to reduce the inclination angle of the working surface; the length of the pseudo-inclined section can be determined according to the inclination projection length of the working surface, the length of the horizontal section and the length of the circular arc section;

[0071] Exemplarily, the pseudo-slope length can be expressed as:

[0072] L3=L w -L1-L2,

[0073] Among them, L3 is the length of the pseudo-slope segment, L w L is the inclined projection length of the working surface, w It can be expressed as:

[0074] L w =L1+L2+L3=N*L S ,

[0075] Wherein, N is the total number of hydraulic supports on the working face.

[0076] In some embodiments, the pseudo-pitch angle is the inclination angle of the working face relative to the inclination direction of the coal seam, and its purpose is to reduce the inclination angle of the working face, thereby reducing the resistance and risk during the mining process. The pseudo-pitch angle can be determined according to the actual length of the working face and the projected length of the pseudo-pitch working face as a whole in the horizontal direction;

[0077] Exemplarily, the pseudo pitch angle can be expressed as:

[0078]

[0079] Where β is the pseudo pitch angle, L Q is the actual length of the pseudo-inclined working surface, L X is the projection length of the pseudo-inclined working surface as a whole in the horizontal direction;

[0080] The actual length of the pseudo-inclined working surface is expressed as:

[0081]

[0082] Among them, α1 is the target reduction angle of the preset working surface inclination;

[0083] The overall projection length of the pseudo-inclined working surface in the horizontal direction is expressed as:

[0084]

[0085] In some embodiments, the target reduction angle of the working face inclination refers to the target value set to reduce the current working face inclination to a certain angle in order to optimize mining conditions, improve safety and efficiency in coal mining engineering operations. The setting of the target reduction angle can be based on a variety of factors, including but not limited to the geological conditions of the coal seam, the performance of the mining equipment, the selection of the mining method, the safety requirements, and the trade-off of economic benefits.

[0086] Specifically, natural conditions such as coal seam thickness, inclination, and geological structure are important factors in determining the inclination of the working face. For example, in steeply inclined coal seams, in order to reduce the collapse of the roof and floor plates and the impact on adjacent coal seams during coal mining, it may be necessary to change the self-flow angle and direction of the coal rock blocks by increasing the inclined length of the working face. In addition, different mining technologies and equipment have different requirements for the inclination of the working face. For example, when using certain specific coal mining machines or tunneling machines, it may be necessary to determine the inclination of the working face based on the performance parameters of the equipment. And the selection of the inclination of the working face also requires a balance between safety and benefits. Too large an inclination may lead to safety problems such as roof and floor collapse and coal wall spalling, while too small an inclination may affect mining efficiency and coal recovery rate. By comprehensively considering safety factors and economic benefits, a target reduction angle for the inclination of the working face can be determined that is both safe and economical.

[0087] Through the above method, the lengths of the horizontal section, arc section and pseudo-inclined section, as well as the pseudo-inclined angle for pseudo-inclined arrangement can be calculated respectively. Then, according to the center distance of the hydraulic support, the number of hydraulic supports required for each section can be determined.

[0088] For example, the number of hydraulic supports required for the horizontal section, arc section and pseudo-inclined section can be expressed as:

[0089]

[0090] Among them, N1 is the number of hydraulic supports in the horizontal section, N2 is the number of hydraulic supports in the arc section, and N3 is the number of hydraulic supports in the pseudo-inclined section.

[0091] S103, arranging the working surface according to the calculation result to form a pseudo inclined working surface composed of a horizontal section working surface, an arc section working surface and a pseudo inclined section working surface.

[0092] It can be understood that the parameters such as the pseudo-pitch angle, horizontal section length, arc section length, pseudo-inclined section length and the corresponding required number of hydraulic supports calculated through the above step S102 can be used to accurately arrange the working face to form a pseudo-pitch working face composed of a horizontal section working face, an arc section working face and a pseudo-inclined section working face, so as to optimize mining conditions and improve safety and efficiency.

[0093] Specifically, according to the calculation results, the position and length of the horizontal section working surface are determined in the coal seam. An appropriate number of hydraulic supports are installed on the horizontal section working surface to ensure the stability and safety of the working surface. According to the length and curvature radius of the arc section, the position and shape of the arc section working surface are determined. As the transition section from the horizontal section to the pseudo-inclined section, the arc section working surface should be designed to ensure the smooth transition of the working surface and the stable support of the support. An appropriate number of hydraulic supports are arranged on the arc section working surface, and the inclination angle of the supports is adjusted to adapt to the curvature change of the arc section. According to the length of the pseudo-inclined section and the pseudo-pitch angle, the position and inclination angle of the pseudo-inclined section working surface are determined. The pseudo-inclined section working surface is the main mining area of ​​the working surface, and its design should ensure stability and efficiency during the mining process. According to the calculation results, an appropriate number of hydraulic supports are arranged on the pseudo-inclined section working surface, and the inclination angle and support height of the supports are adjusted to adapt to the thickness and inclination changes of the coal seam.

[0094] In the embodiment of the present invention, the target coal seam mining working face is divided into a horizontal section, an arc section and a pseudo-inclined section in sequence along the coal seam advancement direction, wherein the horizontal section can release the bottom coal body better, solving the problem that the bottom coal body is usually difficult to release and the coal release rate is low when caving top coal in a coal seam with a steep inclination angle, and the sharp corner part of the original triangular area at the lower end of the working face is alleviated, which can effectively avoid the problem of stress concentration there, making the mining of steeply inclined or steeply inclined coal seams safer; the arc section is a transition section from the horizontal section to the pseudo-inclined section; the pseudo-inclined section can adopt the arrangement method of the pseudo-inclined working face, which can effectively reduce the inclination angle of the mining working face.

[0095] The above method is described below with reference to a specific embodiment. Figures 2 to 6 As shown, Figure 2 It is a structural schematic diagram of the working surface arrangement in an embodiment of the present invention; Figure 3 The main view of the working surface arrangement in the embodiment of the present invention is shown in FIG. Figure 4 A left view of the working surface arrangement in an embodiment of the present invention; Figure 5 A schematic diagram of the arrangement of arc segments of the working surface in an embodiment of the present invention; Figure 6 It is a schematic diagram of the inclined working surface in an embodiment of the present invention.

[0096] Among them, 1 is hydraulic support, 2 is coal seam floor, 3 is coal seam floor, 4 is coal seam, 5 is horizontal section working face, 6 is arc section working face, 7 is pseudo inclined section working face, 8 is transport roadway, 9 is return air roadway. α is coal seam inclination, β is pseudo inclined angle of working face, L S is the center distance of the bracket, L1 is the length of the horizontal segment, L2 is the length of the arc segment, L3 is the length of the pseudo-oblique segment, and L C L is the horizontal width of the arc segment working surface, H L is the arc length at the top beam of the arc segment bracket, X L is the length of the pseudo-inclined working surface projected horizontally.Q is the actual length of the pseudo-pitch working surface of the arc segment, L w is the projection length of the pseudo-inclined working surface of the arc segment along the inclination, and R is the radius of the arc segment (from the top beam of the support).

[0097] In the embodiment of the present invention, by combining the traditional pseudo-inclined working surface and the arc segment working surface arrangement method, the working surface is divided into three sections, namely the horizontal section working surface 5, the arc segment working surface 6 and the pseudo-inclined section working surface 7. Figure 3 As shown, the main view is the view along the coal seam working face advancing direction, and the inclination angle is adjusted by 6-10 sets of hydraulic supports ( Figure 3 The schematic diagram shows 8 flights, which can be determined based on actual calculation results. This is only an example).

[0098] Compared with the traditional pseudo-inclined working surface, the working surface designed in the embodiment of the present invention has an additional arc section working surface and a horizontal section working surface at the bottom. The horizontal section is at the same level, and the arc section is a stage where the lowest level gradually changes to a higher level. Its height change value gradually tends to be stable, and the height difference between the two adjacent hydraulic supports above and below the hydraulic support in the middle of the pseudo-inclined working surface is the same. The arc section and the horizontal section working surface can increase the recovery rate of the inclined lower top coal of the steeply inclined pseudo-inclined working surface. After the inclination angle is changed by the arc section, a pseudo-inclined angle β of the pseudo-inclined working surface is formed between the pseudo-inclined section and the coal seam.

[0099] See also Figure 5 As shown, from the horizontal section working surface 5 to the arc section working surface 6 and then to the pseudo-inclined section working surface 7, two adjacent supports are offset by a certain distance (the supports here are only used for illustration, and this working surface arrangement method requires an optimized design of the bottom of the support), and finally a complete pseudo-inclined working surface is formed by a horizontal section working surface 5, an arc section working surface 6 and a pseudo-inclined section working surface 7.

[0100] Taking a certain actual mining area as an example, the coal seam inclination angle is α=60°, the coal seam thickness H is 10m, and the working face inclination projection length L w The center distance of the hydraulic support is 110m. S The height of the hydraulic support is 1.5m. s The working face angle is reduced to α1 = 45° by this method, which includes:

[0101] Arc segment work surface reference Figure 5 As shown, based on the arc length L at the top beam of the hydraulic support H The calculation formula and coal seam parameters, arc length L at the top beam of the support H It can be expressed as: H＝ N2*L S =8*1.5=12m.

[0102] According to the arc length formula, we can get the radius R of the arc segment at the top beam of the bracket and the horizontal width L of the arc segment working surface. C They are: L C =sinα*R=9.9m.

[0103] Then, the horizontal width of the coal seam minus the horizontal width of the arc section working surface L is calculated. C The length of the horizontal section working surface L1 and the arc length L2 at the base of the arc section bracket are: L1 = H / sinα-L C =1.64m,

[0104] According to the calculation results, it can be determined that the horizontal section working surface requires 1 to 2 sets of hydraulic supports.

[0105] Then, the calculated L1 and L2 are substituted into the calculation formula of the pseudo oblique segment length, and the pseudo oblique segment length L3 can be calculated as L w -L1-L2=92.69m. The number of hydraulic supports required for the pseudo-inclined working surface is further determined as

[0106] Further, the actual length of the working surface is calculated based on Figure 4 as well as Figure 6 Perform geometric reasoning to obtain the length of the horizontal reverse projection of the pseudo-inclined working surface as a whole

[0107] Finally, according to Figure 6 Calculate the pseudo pitch angle of the working surface using geometric relationships

[0108] In the embodiment of the present invention, the target coal seam mining working face is divided into a horizontal section, an arc section and a pseudo-inclined section in sequence along the coal seam advancement direction, wherein the horizontal section can release the bottom coal body better, solving the problem that the bottom coal body is usually difficult to release and the coal release rate is low when caving top coal in a coal seam with a steep inclination angle, and the sharp corner part of the original triangular area at the lower end of the working face is alleviated, which can effectively avoid the problem of stress concentration there, making the mining of steeply inclined or steeply inclined coal seams safer; the arc section is a transition section from the horizontal section to the pseudo-inclined section; the pseudo-inclined section can adopt the arrangement method of the pseudo-inclined working face, which can effectively reduce the inclination angle of the mining working face.

[0109] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0110] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A method for arranging a steeply inclined coal seam mining working face, characterized in that: include: The target coal seam mining working face is divided into horizontal section, arc section and pseudo-inclined section in sequence along the coal seam advancing direction; According to the preset target lowering angle of the working face inclination, combined with the coal seam parameters of the target coal seam and the support parameters of the hydraulic support, the pseudo pitch angle of the working face after the pseudo pitch arrangement is performed to make the working face inclination meet the target lowering angle, as well as the lengths of the horizontal section, the arc section and the pseudo tilt section and the corresponding required number of hydraulic supports are calculated and determined; wherein the coal seam parameters of the target coal seam include at least the coal seam inclination angle, the coal seam thickness and the working face inclination length; the hydraulic support parameters include the support center distance of the hydraulic support and the maximum support height of the hydraulic support; The working surface is arranged according to the calculation results to form a pseudo inclined working surface composed of a horizontal section working surface, an arc section working surface and a pseudo inclined section working surface.

2. The method according to claim 1, characterized in that The horizontal section is located at the bottom of the working face and is used to optimize the discharge efficiency of the coal body at the bottom of the working face; the length of the horizontal section is determined according to the target coal seam thickness and the horizontal width of the arc section; the length of the horizontal section is expressed as: L1=H / sinα-L C , Among them, L1 is the length of the horizontal section, H is the target coal seam thickness, α is the target coal seam inclination, L C It is the width of the arc segment along the horizontal direction.

3. The method according to claim 2, characterized in that The arc section is a transition section from the horizontal section to the pseudo-inclined section, and the inclination angle is adjusted by the transition of a preset number of hydraulic supports; The length of the arc segment is determined according to the arc radius, the height of the hydraulic support and the inclination of the coal seam; the length of the arc segment is expressed as: Among them, L2 is the length of the arc segment, R is the radius of the arc segment, and H s is the height of the hydraulic support, the radius of the arc segment R is calculated based on the arc length formula and the arc length L at the top beam of the hydraulic support H Determine that the arc segment radius R is expressed as: Among them, L H＝ N2*L S , N2 is the number of circular arc hydraulic supports, L S is the center distance of the hydraulic support, and the width L of the arc segment along the horizontal direction C =sinα*R.

4. The method according to claim 3, characterized in that The pseudo-inclined section adopts a pseudo-inclined working surface arrangement method to reduce the inclination angle of the working surface; the length of the pseudo-inclined section is determined according to the inclination projection length of the working surface, the length of the horizontal section and the length of the arc section; the length of the pseudo-inclined section is expressed as: <h2 style=";text-align:left;direction:ltr">L3=L<h2 style=";text-align:left;direction:ltr"> w <h2 style=";text-align:left;direction:ltr"> -L1-L2, Among them, L3 is the length of the pseudo-slope segment, L w L is the inclined projection length of the working surface, w It is expressed as: <h2 style=";text-align:left;direction:ltr">L<h2 style=";text-align:left;direction:ltr"> w <h2 style=";text-align:left;direction:ltr"> (L1+L2+L3) = N*L<h2 style=";text-align:left;direction:ltr"> S <h2 style=";text-align:left;direction:ltr"> , Wherein, N is the total number of hydraulic supports on the working face.

5. The method according to claim 4, characterized in that The number of hydraulic supports required corresponding to the horizontal section, the arc section and the pseudo-inclined section is determined according to the determined lengths of each section and the center distance of the hydraulic supports.

6. The method according to claim 5, characterized in that The pseudo pitch angle is determined according to the actual length of the working surface and the projection length of the pseudo pitch working surface as a whole in the horizontal direction; the pseudo pitch angle is expressed as: Where β is the pseudo pitch angle, L Q is the actual length of the pseudo-inclined working surface, L X is the projection length of the pseudo-inclined working surface as a whole in the horizontal direction; The actual length of the pseudo-inclined working surface is expressed as: Among them, α1 is the target reduction angle of the preset working surface inclination; The overall projection length of the pseudo-inclined working surface in the horizontal direction is expressed as:

7. The method according to any one of claims 1 to 6, characterized in that: The target coal seam is a steeply inclined coal seam with a mining inclination angle greater than 45°, and the thickness of the coal seam is greater than 5m and less than 17m.

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