Method for opening stoping drift of first mining layer in extremely broken ore rock drift filling mining method

Abstract

The invention provides an opening method for a first mining layer stoping drift of an extremely-broken ore rock drift filling mining method, and belongs to the field of mining. The opening method for the first mining layer stoping drift of the extremely-broken ore rock drift filling mining method comprises the following steps that an advanced grouting anchor rod is constructed, a layered transportation roadway is tunneled, and the first mining layer stoping drift of the extremely-broken ore rock drift filling mining method is constructed; primary concrete spraying, cement mortar anchor rod construction, metal mesh laying, steel belt laying, secondary concrete spraying and first steel arch laying are sequentially carried out in the layered haulage roadway; the first steel arch frame comprises a first stand column and a first arch ring. A rectangular hole is formed in the side, close to a to-be-stoped access, of the first arch ring, and reinforcing steel is inserted into the rectangular hole to be connected with all the first steel arch frames; the height of the rectangular hole is higher than that of the rough section of the to-be-stoped access road; and the first stand column close to the opening of the to-be-stoped access and part of the first arch ring lower than the rough section of the to-be-stoped access are removed, and the to-be-stoped access is mined. According to the method, safe support of the layered haulage roadway and safety and stability during construction of the to-be-stoped access opening can be guaranteed.

Description

Technical Field

[0001] The present application relates to the field of mining technology, and in particular to a method for opening a first-layer recovery access in an extremely broken ore and rock access filling mining method. Background Art

[0002] In order to ensure mining safety, most extremely broken medium-thick or thick ore bodies are mined using the downward approach filling mining method. When the downward approach filling mining method is used in actual construction, the construction of the first mining layer is particularly critical, which is related to whether the entire approach plate area can smoothly transfer to the lower layer for continued mining. Under extremely broken ore and rock conditions, the surrounding rock has poor self-stabilization ability, and simple plain shotcrete or shotcrete anchor net support methods cannot effectively support the construction tunnel, making it difficult to ensure its safety and stability, and there are great safety risks. Although the currently used combined support method of "sprayed anchor net + steel belt + steel arch frame" can provide safe and stable support for the stratified transportation tunnels in the first mining layer, when the mining access road is constructed in the first mining layer, it is necessary to temporarily dismantle the support measures at the junction of the stratified transportation tunnel and the access opening. Before the mining access road is constructed for a certain distance and high-strength active support is carried out, the access opening is affected by the removal of support measures such as steel arch frames, the support strength is greatly reduced, the safety risk is increased, and roof collapse occurs from time to time. Not only does it pose a safety hazard, but the subsequent remediation is time-consuming and difficult, which has become a major problem that plagues the safe and efficient production of mines. Summary of the invention

[0003] In view of the technical problems existing in the background technology, the present application provides a method for opening the first mining layer access route in the extremely broken ore and rock access filling mining method. By optimizing the support structure of the layered transport tunnel, the safe support of the layered transport tunnel and the safety and stability of the construction of the opening position of the recovery access route in the layered transport tunnel are guaranteed.

[0004] The present application provides a method for opening a first-layer recovery access road in an extremely broken ore-rock access filling mining method, comprising the following steps: S1, constructing advance grouting anchor rods in the primary mining layer, excavating a layered transport tunnel, and sequentially performing primary concrete spraying, constructing cement mortar anchor rods, laying metal mesh, laying steel belts, secondary concrete spraying, and laying a first steel arch frame in the layered transport tunnel; the first steel arch frame includes a group of first columns and a first arch ring connected to the first columns; S2, a rectangular hole is provided on one side of the first arch ring close to the access road to be mined, and a reinforcing steel is inserted into the rectangular hole to connect all the first steel arch frames; the height of the rectangular hole is higher than the height of the rough section of the access road to be mined; S3. Remove the first column near the opening of the mining access and the part of the first arch ring below the rough section of the mining access, and mine the mining access.

[0005] In the technical solution of the embodiment of the present application, first, the combined support method of "advanced grouting + full-section shotcrete with wire mesh + steel strip connection + steel arch frame" is adopted to support the stratified transportation roadway of the first mining layer, ensuring the long-term safety and stability of the stratified transportation roadway of the first mining layer; then, a rectangular hole is arranged on one side of the first arch ring close to the roadway to be mined, and a reinforcing steel is inserted into the rectangular hole to connect all the first steel arch frames, ensuring that the roadway to be mined can smoothly open the access, guaranteeing the stability of the opening of the roadway to be mined, and realizing the safe and efficient mining of the first mining layer of the downward drift mining method under extremely broken ore and rock conditions.

[0006] In some embodiments, the first arch ring includes a first half arch ring lower than the gross section height of the roadway to be mined and a second half arch ring higher than the gross section height of the roadway to be mined, and the rectangular hole is arranged on the second half arch ring.

[0007] In this embodiment, by setting the first arch ring into two parts, when the roadway to be mined needs to be opened, only the first upright post and the first half arch ring need to be removed, so that the second half arch ring can still play a supporting role; by arranging the rectangular hole on the second half arch ring, it provides favorable conditions for the reinforcement of the reinforcing steel.

[0008] In some embodiments, a first threaded nut lapping structure is arranged between the first upright post and the first arch ring; a second threaded nut lapping structure is arranged between the first half arch ring and the second half arch ring.

[0009] In this embodiment, by arranging the first threaded nut lapping structure, it is convenient for the disassembly and installation of the first upright post and the first arch ring; by arranging the second threaded nut lapping structure, it is convenient for the disassembly and installation of the first half arch ring and the second half arch ring.

[0010] In some embodiments, the height of the rectangular hole is 8 - 12 cm higher than the height of the second threaded nut lapping structure; the length of the rectangular hole is 1 - 2 cm larger than the length of the cross-section of the reinforcing steel, and the width of the rectangular hole is 1 - 2 cm larger than the width of the cross-section of the reinforcing steel.

[0011] In this embodiment, by setting the height of the rectangular hole to be higher than the height of the second threaded nut lapping structure, the reinforcing steel is located at an appropriate position, improving the supporting strength of the supporting structure; by setting the size of the rectangular hole to be slightly larger than the size of the cross-section of the reinforcing steel, while facilitating the insertion of the reinforcing steel into the rectangular hole, it can realize the firm contact between the reinforcing steel and the rectangular hole as much as possible.

[0012] In some embodiments, the distance between adjacent first steel arch frames is 0.8 - 1.2 m.

[0013] In this embodiment, by reasonably controlling the distance between adjacent first steel arch frames, while achieving stable support, the over-density of the first steel arch frames is avoided, thereby reducing the support cost.

[0014] In some embodiments, in step S3, the mining of the stope-to-be-mined specifically includes: first, constructing advance round steel bolts in the stope-to-be-mined, and then carrying out support while mining; the support includes successively carrying out primary shotcrete, constructing the cement mortar bolts, laying the wire mesh, laying the steel strip, laying the second steel arch frame, and secondary shotcrete in the stope-to-be-mined.

[0015] In this embodiment, after the stope-to-be-mined is successfully formed with an access opening, stable support for the stope-to-be-mined is achieved through "advance support + shotcrete with bolts and wire mesh + steel strip + steel arch frame support", thereby realizing safe and efficient mining of the stope-to-be-mined.

[0016] In some embodiments, the diameter of the advance round steel bolts is 30 - 35 mm, the length is 3.0 - 3.5 m, the circumferential spacing is 250 - 350 mm, and the outward inclination angle is 3° - 5°; the thickness of the primary shotcrete is 25 - 35 mm, and the strength is C15; the cement mortar bolts are arranged perpendicular to the wall surface of the stope-to-be-mined, the diameter of the cement mortar bolts is 15 - 25 mm, the length is 1.8 - 2.2 m, and the mesh size is (0.8 - 1.2) m × (0.8 - 1.2) m; the mesh size of the wire mesh is (80 - 120) mm × (80 - 120) mm, and the size is (1.8 - 2.2) m × (0.8 - 1.2) m; the steel strip is a W-shaped steel strip, the length is 2.0 - 2.5 m, the width is 200 - 250 mm, the thickness is 4 - 6 mm, and the spacing between adjacent steel strips is 0.8 - 1.2 m; the thickness of the secondary shotcrete is 25 - 35 mm.

[0017] In this embodiment, by reasonably setting the parameters of each support component in the stope-to-be-mined, safe support for the stope-to-be-mined is achieved, providing favorable conditions for safe and efficient mining of the stope-to-be-mined.

[0018] In some embodiments, in step S1, the outer diameter of the advanced grouting bolt is 30 - 35 mm, the wall thickness is 5 - 7 mm, the length is 3.0 - 3.5 m, the circumferential spacing is 250 - 350 mm, and the outward dip angle is 3° - 5°; the thickness of the first shotcrete is 25 - 35 mm, and the strength is C15; the cement mortar bolt is arranged perpendicular to the wall surface of the stratified haulage roadway, the diameter of the cement mortar bolt is 15 - 25 mm, the length is 1.8 - 2.2 m, and the mesh size is (0.8 - 1.2) m × (0.8 - 1.2) m; the mesh size of the metal mesh is (80 - 120) mm × (80 - 120) mm, and the size is (1.8 - 2.2) m × (0.8 - 1.2) m; the spacing between adjacent steel straps is 0.8 - 1.2 m; the thickness of the second shotcrete is 25 - 35 mm.

[0019] In this embodiment, by reasonably setting the parameters of each support component in the stratified haulage roadway, long-term safe and stable support of the stratified haulage roadway is achieved.

[0020] In some embodiments, a tray is provided at one end of the cement mortar bolt close to the stratified haulage roadway or the stope heading to be mined.

[0021] In this embodiment, by providing a tray at one end of the cement mortar bolt close to the roadway, reinforcement between the cement mortar bolt, the metal mesh and the steel strap is achieved through the tray, improving the support effect.

[0022] In some embodiments, the size of the rough section of the stratified haulage roadway is 4.6 m × 3.9 m, and the size of the net section after support is 4 × 3.6 m; the size of the rough section of the stope heading to be mined is 3.8 m × 3.3 m, and the size of the net section after support is 3.2 × 3.0 m.

[0023] In this embodiment, by reasonably setting the sizes of the rough section and the net section after support of the stratified haulage roadway, smooth transportation of ore is facilitated while achieving firm support; by reasonably setting the sizes of the rough section and the net section after support of the stope heading to be mined, favorable conditions are provided for the reinforcement of the reinforcement steel, thereby achieving smooth and safe opening and efficient and safe mining of the stope heading to be mined.

[0024] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the following specifically illustrates the specific embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] To more clearly illustrate the technical solution of this application, the attached drawings used in this application will be briefly introduced below. Obviously, the attached drawings described below are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other attached drawings can be obtained based on these attached drawings.

[0026] Figure 1 Schematic diagram of the layout of the first mining layer in the panel of the downward drift backfill mining method in the embodiment of this application; Figure 2 Front view of the opening of the drift in the stratified haulage roadway in the embodiment of this application; Figure 3 For Figure 2 Schematic diagram of the I-I cross-section in Figure 4 For Figure 2 Schematic diagram of the II-II cross-section in Figure 5 Full-section view of the drift to be mined in the embodiment of this application; Figure 6 Schematic diagram of the first threaded nut lapping structure in the embodiment of this application; Figure 7 Schematic diagram of "full-section shotcrete mesh + steel strip connection" of the stratified haulage roadway in the embodiment of this application; Figure 8 For Figure 3 Enlarged view of location A in Explanation of reference numerals: 1 - Advance grouting bolt; 2 - Stratified haulage roadway; 3 - Cement mortar bolt; 4 - Metal mesh; 5 - Steel strip; 6 - First steel arch; 7 - Reinforcing steel; 8 - Drift to be mined; 9 - Advance round steel bolt; 10 - First threaded nut lapping structure; 11 - Second threaded nut lapping structure; 12 - Cross-cut outside the vein; 13 - Second steel arch; 14 - Tray; 15 - Surrounding rock; 16 - Panel connection drift; 17 - Haulage roadway; 61 - First column; 62 - First arch ring; 63 - Rectangular hole; 101 - First T-shaped bolt; 102 - First nut; 103 - First small washer; 104 - First large washer; 131 - Second column; 132 - Second arch ring. Detailed implementation manners

[0027] The embodiments of the technical solution of this application will be described in detail below in conjunction with the attached drawings. The following embodiments are only used to more clearly illustrate the technical solution of this application, so they are only examples and cannot be used to limit the protection scope of this application.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0029] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order, or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "a plurality" is more than two, unless otherwise specifically and clearly defined.

[0030] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0031] In the description of the embodiments of this application, the orientation or positional relationship indicated by technical terms such as "length", "width", "thickness", "upper", "lower", "vertical", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of this application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation on the embodiments of this application.

[0032] In the description of the embodiments of this application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "coupled", "fixed", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0033] For most medium-thick and above ore bodies with extremely broken conditions, the downward drift filling mining method is mostly used for mining. Under the conditions of extremely broken ore and rock, the surrounding rock has poor self-stabilizing ability, and the combined support method of "shotcrete-bolt-mesh + steel strip + steel arch" is usually adopted. Although this support method can provide safe and stable support for the sublevel haulage roadway of the first mining layer, when constructing the stoping drift in the first mining layer, it is necessary to temporarily remove the support measures at the junction of the sublevel haulage roadway and the drift opening. At present, when the support measures at the junction of the sublevel haulage roadway and the drift opening are temporarily removed using the combined support method of "shotcrete-bolt-mesh + steel strip + steel arch", there is a risk of roof collapse at the drift opening.

[0034] In order to solve the technical problem that there is a risk of roof collapse at the drift opening when the support measures at the junction of the sublevel haulage roadway and the drift opening are temporarily removed, the present application provides a method for opening the stoping drift of the first mining layer in the extremely broken ore and rock drift filling mining method. Among them, first, the combined support method of "advance grouting + full-section shotcrete-bolt-mesh + steel strip connection + steel arch" is adopted to support the sublevel haulage roadway of the first mining layer, ensuring the long-term safety and stability of the sublevel haulage roadway of the first mining layer; then, a rectangular hole is set on one side of the first arch ring close to the stoping drift to be mined, and a reinforcing steel connection is inserted into the rectangular hole to connect all the first steel arches, ensuring that the stoping drift to be mined can smoothly open the drift entrance and guaranteeing the stability of the opening of the stoping drift to be mined, realizing the safe and efficient mining of the first mining layer of the downward drift mining method under the conditions of extremely broken ore and rock. This method shows excellent adaptability under extremely broken ore and rock and complex geological conditions, and has broad application prospects and popularization value.

[0035] Please refer to Figure 1 In this application, the downward drift filling mining method is adopted for mining. During the mining process, in order to reasonably plan the production area and optimize the production system, the ore body is divided into panels, and mining is carried out with the panel as the unit. A panel access drift 16 is set between adjacent panels. Specifically, an off-vein haulage roadway 12 arranged along the ore body strike is constructed in the surrounding rock 15 outside the panel, a sublevel haulage roadway 2 arranged along the ore body strike is constructed in the panel, and several stoping drifts 8 to be mined are divided in the panel. Ore is mined by opening the stoping drifts 8 from the sublevel haulage roadway 2. The stoping drifts 8 are arranged perpendicular to the ore body strike. Considering the actual production situation and comprehensively considering the drift division and production capacity requirements, a mining form of mining every other or every two is adopted. For the convenience of transportation, a haulage roadway 17 can be set in the panel, and the ore is transported to the off-vein haulage roadway 12 for ore extraction through the sublevel haulage roadway 2, the panel access drift 16, and the haulage roadway 17.

[0036] Please refer to Figures 2 - 4 For the method for opening the stoping drift of the first mining layer in the extremely broken ore and rock drift filling mining method provided by the embodiment of the present application, it includes the following steps: S1. Advance grouting bolts 1 are constructed in the first mining layer, and the stratified haulage roadway 2 is driven. In the stratified haulage roadway 2, shotcrete is applied for the first time, mortar bolts 3 are constructed, metal mesh sheets 4 are laid, steel straps 5 are laid, shotcrete is applied for the second time, and the first steel arch 6 is laid. The first steel arch 6 includes a group of first columns 61 and a first arch ring 62 connected to the first columns 61. Specifically, at the opening position of the stratified haulage roadway 2, advance drilling is carried out in the direction of the arch ahead with an out-of-angle along the excavation contour line outside the opening. After the drilling construction is completed, advance grouting bolts 1 are installed to form pre-anchoring, and then grouting construction is carried out. After the grout solidifies, the driving operation of the stratified haulage roadway 2 is carried out. After the stratified haulage roadway 2 is driven, ventilation and mucking are immediately carried out, and then shotcrete is applied to the entire section for the first time. After the first shotcrete is completed, the drilling construction of the mortar bolts 3 is carried out. After the mortar bolts 3 are inserted into the holes, the metal mesh sheets 4 and the steel straps 5 are laid. The steel straps 5 are arranged along the trend of the stratified haulage roadway 2, and the steel straps 5 are overlapped with the mortar bolts 3, thus completing the construction of "shotcrete, bolts and mesh + steel straps". Then, the second shotcrete operation is carried out to ensure that the surface of the second shotcrete layer is relatively flat, and the support members such as the mortar bolts 3, the metal mesh sheets 4 and the steel straps 5 are basically not exposed, meeting the support safety standards. Then, the first steel arch 6 is installed. The advance grouting bolts 1 are hollow seamless steel pipes. Both the first columns 61 and the first arch ring 62 are made of I-beams of model 25a.

[0037] S2. A rectangular hole 63 is provided on one side of the first arch ring 62 close to the stope access 8 to be mined. A reinforcing steel 7 is inserted into the rectangular hole 63 to connect all the first steel arches 6. If stope accesses 8 to be mined are provided on both sides of the stratified haulage roadway 2, rectangular holes 63 need to be provided on both sides of the first arch ring 62 close to the stope accesses 8 to be mined, and the reinforcing steel 7 is inserted into the rectangular holes 63 on both sides to connect all the first steel arches 6. The height of the rectangular hole 63 is higher than the height of the rough section of the stope access 8 to be mined. Specifically, the rectangular hole 63 is formed on the first arch ring 62 by cutting, and the reinforcing steel 7 is inserted into the rectangular hole 63 to connect all the first steel arches 6. The reinforcing steel 7 is made of I-beams of model 16.

[0038] S3. The first columns 61 close to the opening of the stope access 8 to be mined and a part of the first arch ring 62 lower than the rough section of the stope access 8 to be mined are removed, and the stope access 8 to be mined is mined. Specifically, when the stope access 8 to be mined is ready to open, the first columns 61 and the part of the first arch ring 62 lower than the rough section of the stope access 8 to be mined within the coverage of the rough section of the stope access 8 to be mined are removed. At this time, the remaining part of the first arch ring 62 at the top of the opening of the stope access 8 to be mined is connected to the first steel arches 6 at other parts not removed through the reinforcing steel 7 to form an integral structure.

[0039] In the technical solution of the embodiment of the present application, first, the combined support method of "advanced grouting + full-section shotcrete with wire mesh + steel strip connection + steel arch" is adopted to support the layered transportation roadway 2 of the first mining layer. This support method has good active support effect and high support strength, and can ensure the long-term safety and stability of the layered transportation roadway 2 of the first mining layer. Then, a rectangular hole 63 is provided on one side of the first arch ring 62 close to the stope approach 8 to be mined, and a reinforcing steel 7 is inserted into the rectangular hole 63 to connect all the first steel arch frames 6, so that all the first steel arch frames 6 form an integral structure. In this way, on the one hand, the overall support strength of the layered transportation roadway 2 is enhanced, and at the same time, it helps to increase the step distance of the first steel arch frame 6 and optimize the support cost. On the other hand, when the stope approach 8 to be mined is ready to be opened, when the first column 61 within the covered area of the rough section of the stope approach 8 to be mined and part of the first arch ring 62 below the rough section of the stope approach 8 to be mined are removed, at this time, the remaining part of the first arch ring 62 at the top of the opening of the stope approach 8 to be mined is connected to the first steel arch frames 6 at other non-removed parts through the reinforcing steel 7 to form an integral structure, so that the roof at the opening of the stope approach 8 to be mined forms an overall combined stress plane, which can evenly distribute the pressure on the roof of the stope approach 8 at the first steel arch frame 6 where part of the first arch ring 62 is disassembled to the adjacent complete first steel arch frames 6, avoiding the collapse of the roof of the stope approach 8 caused by local pressure concentration, ensuring that the stope approach 8 can be smoothly opened, guaranteeing the stability at the opening of the stope approach 8, and realizing the safe and efficient mining of the first mining layer of the downward drift mining method under extremely broken ore and rock conditions. At the same time, it can prevent the remaining part of the first arch ring 62 at the top of the opening of the stope approach 8 to be mined from falling, so that it can still play a good supporting role, keeping the roof at the opening position of the stope approach 8 stable, and further realizing the safe and efficient mining of the first mining layer. That is, the present application optimizes the support structure of the layered transportation roadway 2 to ensure the safety and stability during the construction of the opening position of the stope approach 8 in the layered transportation roadway 2.

[0040] Furthermore, in the embodiment of the present application, as Figure 3 shown, the first arch ring 62 includes a first semi-arch ring lower than the rough section height of the stope approach 8 to be mined and a second semi-arch ring higher than the rough section height of the stope approach 8 to be mined, and the rectangular hole 63 is provided on the second semi-arch ring. If stope approaches 8 to be mined are provided on both sides of the layered transportation roadway 2, the parts of both sides of the first arch ring 62 lower than the rough section height of the stope approach 8 to be mined are both called first semi-arch rings, that is, the first arch ring 62 includes two first semi-arch rings and one second semi-arch ring.

[0041] In the technical solution of the embodiment of the present application, by setting the first arch ring 62 into a first semi-arch ring lower than the gross section height of the stope heading 8 to be mined and a second semi-arch ring higher than the gross section height of the stope heading 8 to be mined, when the stope heading 8 to be mined needs to be opened, only the first upright post 61 and the first semi-arch ring need to be removed, so that the second semi-arch ring can still play a supporting role. By arranging the rectangular holes 63 on the second semi-arch ring, even when the first semi-arch ring is removed, it can still ensure that the reinforcement steel 7 exists at the top of the stratified haulage roadway 2 and is connected to the intact first steel arch frame 6 at other parts that are not removed to form an integral structure, improving the support effect and realizing the smooth opening and efficient mining of the stope heading 8 to be mined.

[0042] Furthermore, in the embodiment of the present application, as Figure 3 shown, a first threaded nut lapping structure 10 is provided between the first upright post 61 and the first arch ring 62; a second threaded nut lapping structure 11 is provided between the first semi-arch ring and the second semi-arch ring. Specifically, as Figure 6 shown, the first threaded nut lapping structure 10 includes a first T-shaped bolt 101 and a first nut 102. Through holes are provided at the connection positions of the first upright post 61 and the first arch ring 62. The first T-shaped bolt 101 passes through the through holes provided on the first upright post 61 and the first arch ring 62 and is fixed by the first nut 102 to realize the detachable connection between the first upright post 61 and the first arch ring 62; a first large gasket 104 is provided at the contact position between the first T-shaped bolt 101 and the first upright post 61; a first small gasket 103 is provided at the contact position between the first nut 102 and the first arch ring 62. The second threaded nut lapping structure 11 is similar to the structure of the first threaded nut lapping structure 10. Specifically, the second threaded nut lapping structure 11 includes a second T-shaped bolt and a second nut. Through holes are provided at the connection positions of the first semi-arch ring and the second semi-arch ring. The second T-shaped bolt passes through the through holes provided on the first semi-arch ring and the second semi-arch ring and is fixed by the second nut to realize the detachable connection between the first semi-arch ring and the second semi-arch ring; a second large gasket is provided at the contact position between the second T-shaped bolt and the first semi-arch ring; a second small gasket is provided at the contact position between the second nut and the second semi-arch ring.

[0043] In the technical solution of the embodiment of the present application, by providing the first threaded nut lapping structure 10 at the connection position between the first upright post 61 and the first arch ring 62, it is convenient for the disassembly and installation of the first upright post 61 and the first arch ring 62. By providing the second threaded nut lapping structure 11 at the connection position between the first semi-arch ring and the second semi-arch ring, it is convenient for the disassembly and installation of the first semi-arch ring and the second semi-arch ring. When the stope heading 8 to be mined is ready to be opened, the first upright post 61 and the first semi-arch ring can be quickly removed through the first threaded nut lapping structure 10 and the second threaded nut lapping structure 11, and then the opening and mining of the stope heading 8 to be mined can be quickly realized.

[0044] Furthermore, in the embodiment of the present application, asFigure 3 As shown, the height of the rectangular hole 63 is 8 - 12 cm higher than the height of the second threaded nut lapping structure 11; the length of the rectangular hole 63 is 1 - 2 cm larger than the length of the cross-section of the reinforcing steel 7, and the width of the rectangular hole 63 is 1 - 2 cm larger than the width of the cross-section of the reinforcing steel 7. Specifically, the length of the rectangular hole 63 is 170 mm, the width is 98 mm, the length of the cross-section of the reinforcing steel 7 is 160 mm, and the width of the cross-section is 88 mm.

[0045] In the technical solution of the embodiment of the present application, by setting the height of the rectangular hole 63 to be higher than the height of the second threaded nut lapping structure 11, the reinforcing steel 7 is located at an appropriate position, improving the support strength of the support structure. By setting the size of the rectangular hole 63 to be slightly larger than the size of the cross-section of the reinforcing steel 7, while facilitating the insertion of the reinforcing steel 7 into the rectangular hole 63, it can achieve a firm contact between the reinforcing steel 7 and the rectangular hole 63 as much as possible, enabling the reinforcing steel 7 to play a better support role. In order to further improve the contact firmness between the reinforcing steel 7 and the rectangular hole 63, the rectangular hole 63 and the reinforcing steel 7 can be welded.

[0046] Further, in the embodiment of the present application, as Figure 2 shown, the distance (i.e., the step distance) between adjacent first steel arch frames 6 is 0.8 - 1.2 m, preferably 1 m. Specifically, in a locally more fragmented area, the distance between adjacent first steel arch frames 6 can be appropriately reduced, and the first arch ring 62 is processed according to the arched shape of the layered transportation roadway 2.

[0047] In the technical solution of the embodiment of the present application, by reasonably controlling the distance between adjacent first steel arch frames 6, while achieving stable support, it avoids the excessive density of the first steel arch frames 6 and increases the support cost.

[0048] Further, in the embodiment of the present application, as Figure 5As shown in the figure, the mining of the stope heading 8 in step S3 is specifically as follows: First, advance round steel bolts 9 are constructed in the stope heading 8, and then mining and support are carried out simultaneously. The support includes spraying concrete for the first time, constructing cement mortar bolts 3, laying wire mesh 4, laying steel strips 5, laying the second steel arch 13, and spraying concrete for the second time in the stope heading 8 in sequence. The stope heading 8 is a temporary construction project. After the stope heading 8 is constructed according to the designed length, filling treatment is carried out. Therefore, when carrying out advance support, a non-grouting form can be adopted. The stope heading 8 can be normally mined according to the construction sequence of "advance pre-support + shotcrete with bolts and wire mesh + steel strip + steel arch support". Specifically, at the opening position of the stope heading 8, advance drilling is carried out first at an outside corner along the excavation contour line towards the arch front. After the drilling construction is completed, advance round steel bolts 9 are installed to form pre-anchoring; the stope heading 8 is mined, and support is carried out simultaneously during mining. After mining a preset distance, ventilation and mucking are immediately carried out. Then, the rough section of the stope heading 8 is sprayed with concrete for the first time. After the first spraying of concrete is completed, drilling construction of the cement mortar bolts 3 is carried out. After the cement mortar bolts 3 are inserted into the holes, the wire mesh 4 and the steel strips 5 are laid. The steel strips 5 are arranged along the direction of the stope heading 8, and the steel strips 5 are lapped with the cement mortar bolts 3, thus completing the construction of "shotcrete with bolts and wire mesh + steel strip". Then, the second steel arch 13 is laid, and the second spraying of concrete operation is carried out to ensure that the surface of the second sprayed concrete layer is relatively flat, and there is basically no exposed phenomenon for the support members such as the cement mortar bolts 3, the wire mesh 4, and the steel strips 5, meeting the support safety standard. The second steel arch 13 includes a group of second columns 131 and a second arch ring 132. A first threaded nut lapping structure 10 is provided at the connection of the second columns 131 and the second arch ring 132; both the second columns 131 and the second arch ring 132 are made of I-beams of model 25a.

[0049] In the technical solution of the embodiment of the present application, after the stope heading 8 is successfully formed at the inlet, stable support of the stope heading 8 is achieved through "advance support + shotcrete with bolts and wire mesh + steel strip + steel arch support", and then safe and efficient mining of the stope heading 8 is realized.

[0050] Further, in the embodiment of the present application, as Figure 5As shown in the figure, the diameter of the advanced round steel bolt 9 in the stope heading 8 to be mined is 30 - 35 mm, the length is 3.0 - 3.5 m, the circumferential spacing is 250 - 350 mm, and the outward dip angle is 3° - 5°. Preferably, the diameter of the advanced round steel bolt 9 is 32 mm, the length is 3 m, the circumferential spacing is 300 mm, and the outward dip angle is 4°; the thickness of the first shotcrete is 25 - 35 mm, preferably 30 mm, and the strength is C15; the cement mortar bolt 3 is arranged perpendicular to the wall surface of the stope heading 8 to be mined. The diameter of the cement mortar bolt 3 is 15 - 25 mm, the length is 1.8 - 2.2 m, and the mesh size is (0.8 - 1.2) m × (0.8 - 1.2) m. Preferably, the diameter of the cement mortar bolt 3 is 20 mm, the length is 2 m, and the mesh size is 1 m × 1 m; the mesh size of the metal mesh 4 is (80 - 120) mm × (80 - 120) mm, and the size is (1.8 - 2.2) m × (0.8 - 1.2) m. Preferably, the mesh size of the metal mesh 4 is 1 m × 1 m, and the size is 2 m × 1 m. The metal mesh 4 is welded with steel bars with a diameter of 8 mm; the steel strip 5 is a W-shaped steel strip, the length is 2.0 - 2.5 m, the width is 200 - 250 mm, and the thickness is 4 - 6 mm. Preferably, the length of the steel strip 5 is 2 m, the width is 220 mm, and the thickness is 5 mm. The spacing between adjacent steel strips 5 is 0.8 - 1.2 m, preferably 1 m; the thickness of the second shotcrete is 25 - 35 mm.

[0051] In the technical solution of the embodiment of the present application, by reasonably setting the parameters of the advanced round steel bolt 9, the cement mortar bolt 3, the metal mesh 4, the steel strip 5, the first shotcrete and the second shotcrete, the safe support of the stope heading 8 to be mined is realized, providing favorable conditions for the safe and efficient mining of the stope heading 8 to be mined.

[0052] Furthermore, in the embodiment of the present application, as Figure 3As shown in the figure, in step S1, the outer diameter of the advanced grouting bolt 1 is 30 - 35 mm, the wall thickness is 5 - 7 mm, the length is 3.0 - 3.5 m, the circumferential spacing is 250 - 350 mm, and the external insertion angle is 3° - 5°. Preferably, the outer diameter of the advanced grouting bolt 1 is 32 mm, the wall thickness is 6 mm, the length is 3 m, the circumferential spacing is 300 mm, and the external insertion angle is 4°. The thickness of the first shotcrete is 25 - 35 mm, preferably 30 mm, and the strength is C15. The cement mortar bolt 3 is arranged perpendicular to the wall surface of the stratified transportation roadway 2. The diameter of the cement mortar bolt 3 is 15 - 25 mm, the length is 1.8 - 2.2 m, and the mesh size is (0.8 - 1.2) m × (0.8 - 1.2) m. Preferably, the diameter of the cement mortar bolt 3 is 20 mm, the length is 2 m, and the mesh size is 1 m × 1 m. The mesh size of the metal mesh 4 is (80 - 120) mm × (80 - 120) mm, and the size is (1.8 - 2.2) m × (0.8 - 1.2) m. Preferably, the mesh size of the metal mesh 4 is 1 m × 1 m, the size is 2 m × 1 m, and the metal mesh 4 is welded with steel bars with a diameter of 8 mm. The steel strip 5 is a W-shaped steel strip, the length is 2.0 - 2.5 m, the width is 200 - 250 mm, and the thickness is 4 - 6 mm. Preferably, the length of the steel strip 5 is 2 m, the width is 220 mm, and the thickness is 5 mm. The spacing between adjacent steel strips 5 is 0.8 - 1.2 m, preferably 1 m. The thickness of the second shotcrete is 25 - 35 mm.

[0053] In the technical solution of the embodiment of the present application, by reasonably setting the parameters of the advanced grouting bolt 1, the cement mortar bolt 3, the metal mesh 4, the steel strip 5, the first shotcrete, and the second shotcrete, long-term safe and stable support of the stratified transportation roadway 2 is achieved.

[0054] Furthermore, in the embodiment of the present application, as Figure 7 shown, a tray 14 is provided at one end of the cement mortar bolt 3 close to the stratified transportation roadway 2 or the stope heading 8 to be mined. Specifically, the tray 14 is installed at the end of the cement mortar bolt 3 close to the roadway, and the tray 14 presses on the metal mesh 4 and the steel strip 5.

[0055] In the technical solution of the embodiment of the present application, by providing the tray 14 at one end of the cement mortar bolt 3 close to the roadway, the reinforcement between the cement mortar bolt 3, the metal mesh 4, and the steel strip 5 is realized through the tray 14, and the support effect is improved.

[0056] Furthermore, in the embodiment of the present application, the size of the rough section of the stratified transportation roadway 2 is 4.6 m × 3.9 m, and the size of the net section after support is 4 × 3.6 m; the size of the rough section of the stope heading 8 to be mined is 3.8 m × 3.3 m, and the size of the net section after support is 3.2 × 3.0 m.

[0057] In the technical solution of the embodiment of the present application, by reasonably setting the sizes of the rough cross-section and the net cross-section after support of the layered transportation roadway 2, while achieving firm support, it is convenient for the smooth transportation of ore. By reasonably setting the sizes of the rough cross-section and the net cross-section after support of the stope heading 8 to be mined, making them smaller than the sizes of the rough cross-section and the net cross-section after support of the layered transportation roadway 2, it provides favorable conditions for the reinforcement of the reinforcement steel 7, and then realizes the smooth and safe opening and efficient and safe mining of the stope heading 8 to be mined.

[0058] Please refer to Figures 1 - 7 , according to one or more embodiments of the present application, the present application first adopts a combined support method of "advance grouting + full-section shotcrete with wire mesh + steel strip connection + steel arch frame" to support the layered transportation roadway 2 of the first mining layer, which can ensure the long-term safety and stability of the layered transportation roadway 2 of the first mining layer; then a rectangular hole 63 is set on one side of the first arch ring 62 close to the stope heading 8 to be mined, and a reinforcement steel 7 is inserted into the rectangular hole 63 to connect all the first steel arch frames 6, which not only enhances the overall support strength of the layered transportation roadway 2, but also when the stope heading 8 to be mined is ready to open, when removing the first upright column 61 within the rough cross-section coverage of the stope heading 8 to be mined and part of the first arch ring 62 below the rough cross-section of the stope heading 8 to be mined, it forms an overall combined stress plane on the roof at the opening of the stope heading 8 to be mined, ensuring that the stope heading 8 to be mined can smoothly open the access, guaranteeing the stability at the opening of the stope heading 8 to be mined, and realizing the safe and efficient mining of the first mining layer of the downward drift mining method under extremely broken ore and rock conditions; by setting the first threaded nut lapping structure 10 and the second threaded nut lapping structure 11, it is convenient for the disassembly and installation of the first upright column 61, the first arch ring 62, the first half arch ring and the second half arch ring, and then quickly realizes the opening and mining of the stope heading 8 to be mined.

[0059] It should be noted that the present application is not limited to the above-mentioned implementation manners. The above-mentioned implementation manners are only examples, and implementation manners with the same constituent elements in essence as the technical idea and the same function and effect within the technical solution scope of the present application are all included in the technical scope of the present application. In addition, within the scope not departing from the gist of the present application, various deformations that can be thought of by those skilled in the art are applied to the implementation manners, and other manners constructed by combining some constituent elements in the implementation manners are also included in the scope of the present application.

Claims

1. A method for opening the first mining layer recovery route in the extremely broken ore route filling mining method, characterized in that: The following steps are involved: S1, constructing advance grouting anchor rods in the primary mining layer, excavating a layered transport tunnel, and sequentially performing primary concrete spraying, constructing cement mortar anchor rods, laying metal mesh, laying steel belts, secondary concrete spraying, and laying a first steel arch frame in the layered transport tunnel; the first steel arch frame includes a group of first columns and a first arch ring connected to the first columns; S2, a rectangular hole is provided on one side of the first arch ring close to the access road to be mined, and a reinforcing steel is inserted into the rectangular hole to connect all the first steel arch frames; the height of the rectangular hole is higher than the height of the rough section of the access road to be mined; S3. Remove the first column near the opening of the mining access and the part of the first arch ring below the rough section of the mining access, and mine the mining access.

2. The method for opening the first mining layer recovery access road of the extremely broken ore rock access filling mining method according to claim 1 is characterized in that: The first arch ring includes a first half arch ring lower than the rough cross-sectional height of the access road to be mined and a second half arch ring higher than the rough cross-sectional height of the access road to be mined, and the rectangular hole is arranged on the second half arch ring.

3. The method for opening the first mining layer recovery route of the extremely broken ore route filling mining method according to claim 2 is characterized in that: A first threaded nut overlapping structure is provided between the first column and the first arch ring; and a second threaded nut overlapping structure is provided between the first semi-arch ring and the second semi-arch ring.

4. The method for opening the first mining layer recovery access road of the extremely broken ore rock access road filling mining method according to claim 3 is characterized in that: The height of the rectangular hole is 8-12 cm higher than the height of the second threaded nut overlap structure; the length of the rectangular hole is 1-2 cm larger than the length of the reinforcing steel cross section, and the width of the rectangular hole is 1-2 cm larger than the width of the reinforcing steel cross section.

5. The method for opening the first mining layer recovery route of the extremely broken ore route filling mining method according to claim 1 is characterized in that: The distance between adjacent first steel arch frames is 0.8-1.2 m.

6. The method for opening the first mining layer recovery route of the extremely broken ore route filling mining method according to claim 1 is characterized in that: The specific steps of mining the access road to be mined in step S3 are as follows: first, an advanced round steel anchor is constructed in the access road to be mined, and then mining and supporting are performed simultaneously; the support includes spraying concrete once, constructing the cement mortar anchor, laying the metal mesh, laying the steel belt, laying the second steel arch, and spraying concrete twice in sequence in the access road to be mined.

7. The method for opening the first mining layer recovery access road of the extremely broken ore rock access filling mining method according to claim 6 is characterized in that: The diameter of the advanced round steel anchor rod is 30-35mm, the length is 3.0-3.5m, the circumferential spacing is 250-350mm, and the external insertion angle is 3°-5°; the thickness of the one-time shotcrete is 25-35mm, and the strength is C15; the cement mortar anchor rod is arranged perpendicular to the wall of the access road to be mined, the diameter of the cement mortar anchor rod is 15-25mm, the length is 1.8-2.2m, and the mesh size is (0.8-1.2)m ×(0.8-1.2)m; the mesh size of the metal mesh is (80-120)mm×(80-120)mm, and the size is (1.8-2.2)m×(0.8-1.2)m; the steel belt is a W-shaped steel belt with a length of 2.0-2.5m, a width of 200-250mm, a thickness of 4-6mm, and a spacing between adjacent steel belts of 0.8-1.2m; the thickness of the secondary sprayed concrete is 25-35mm.

8. The method for opening the first mining layer recovery route of the extremely broken ore route filling mining method according to claim 1 is characterized in that: In step S1, the outer diameter of the advance grouting anchor rod is 30-35mm, the wall thickness is 5-7mm, the length is 3.0-3.5m, the circumferential spacing is 250-350mm, and the external insertion angle is 3°-5°; the thickness of the first sprayed concrete is 25-35mm, and the strength is C15; the cement mortar anchor rod is arranged perpendicular to the wall of the layered transport laneway, the diameter of the cement mortar anchor rod is 15-25mm, the length is 1.8-2.2m, and the mesh size is (0.8-1.2)m×(0.8-1.2)m; the mesh size of the metal mesh is (80-120)mm×(80-120)mm, and the size is (1.8-2.2)m×(0.8-1.2)m; the spacing between adjacent steel belts is 0.8-1.2m; the thickness of the second sprayed concrete is 25-35mm.

9. The method for opening the first mining layer recovery access road of the extremely broken ore rock access road filling mining method according to claim 6 is characterized in that: A tray is provided at one end of the cement mortar anchor rod close to the layered transport tunnel or the access road to be mined.

10. The method for opening the first mining layer recovery route of the extremely broken ore route filling mining method according to claim 1 is characterized in that: The gross cross-sectional dimensions of the layered transport tunnel are 4.6m×3.9m, and the net cross-sectional dimensions after support are 4×3.6m; the gross cross-sectional dimensions of the access road to be mined are 3.8m×3.3m, and the net cross-sectional dimensions after support are 3.2×3.0m.

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