A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock

Abstract

This application mentions a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock, belonging to the field of underground mining methods. For gently inclined ore bodies with broken hanging wall surrounding rock, through steps such as stope layout, development, cutting, stoping, and filling, a protective layer is left on the hanging wall of the ore body, and combined support with bolts and cable bolts is used to ensure the stability of the protective layer and the hanging wall surrounding rock; the ore rooms within a stage are mined from bottom to top, and in a panel, the ore rooms in the same section are mined "one by one with one interval", ensuring the stoping intensity and efficiency; the throwing effect is used to collapse the ore into the ore receiving space of the trench at the bottom of the section, overcoming the problem of stope transportation where the self-weight of the ore cannot be used for gravity chute in gently inclined ore bodies. The method of the present invention can take into account the safety problems caused by broken hanging wall surrounding rock and the mining efficiency, and meet the mining economy, high efficiency, and safety of such ore deposits.

Description

Technical Field

[0001] The present invention relates to the field of underground mining methods, and particularly to a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock. Background Art

[0002] With the rapid development of social economy, the intensity of mineral resource development continues to increase. Some easily mined ore bodies with good grades, high values, stable surrounding rock, and good occurrence conditions have been exhausted, and the proportion of ore deposits with relatively poor mining conditions is gradually increasing. For example, for gently inclined medium-thick to thick ore bodies, the traditional methods for mining such ore bodies are the full mining method and the room-and-pillar method. However, due to the conditions of broken ore bodies and hanging wall surrounding rock, the traditional mining methods are no longer applicable. The downward slicing drift mining method can technically meet the mining requirements, but the mining process is complex and the mining cost is high. Especially when the grade and value of such ore bodies are low, the downward slicing mining method cannot meet the mining requirements economically.

[0003] Chinese Patent CN 118933759A discloses a mining method for inclined medium-thick ore bodies with broken hanging wall, mainly aiming at broken ore bodies with inclined ore body dip angles. The stage is divided into sublevels, and the sublevel stope section is approximately rhombic. A connecting crosscut roadway is excavated at the intersection of the hanging wall ore and rock, and shotcrete-bolt-mesh support is used to maintain the stability of the roof. A triangular sill pillar is left between the stage haulage roadways, and no crown pillar is set between the stage haulage roadways. It is not applicable to the hanging wall surrounding rock that already has a broken phenomenon and gently inclined medium-thick ore bodies with dip angles of 11 - 22°, which is not conducive to the stability of its hanging wall surrounding rock and the ore is prone to dilution. Moreover, the roadway structure of each sublevel is complex, the development workload is relatively large, and the cost is relatively high. Most importantly, the stope structure in the above patent cannot solve the problem of gently inclined broken ore bodies, the stope production capacity is low, and the ore handling in the stope is difficult.

[0004] Therefore, it is necessary to develop a new mining method that can take into account the safety problems caused by broken hanging wall surrounding rock and the mining efficiency, and meet the mining economy, efficiency, and safety of such ore deposits. Summary of the Invention

[0005] Technical problems to be solved: In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention proposes a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock, aiming to solve the technical problems such as the difficulty in balancing the mining safety and economy of traditional mining methods for such ore bodies and the high mining cost.

[0006] Technical solution:

[0007] The present invention proposes a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock, and the steps are as follows:

[0008] S1. In a certain stage, a plurality of sublevels are arranged along the vertical direction c of the ore body, and a plurality of panels are divided along the strike direction a of the ore body; a plurality of ore rooms are arranged along the strike direction a within the sublevels of the same panel; an interval crown pillar is arranged between adjacent ore rooms along the vertical direction c of the ore body, and panel pillars are left at both ends of the panel along the strike direction a of the ore body.

[0009] S2. Between the bottom of the stage and each sublevel, stage haulage roadways are opened along the strike direction a of the ore body. At the position corresponding to the center line of the panel pillar in the stage haulage roadway, after driving the stope access roadway, the drift is driven along the strike direction a of the ore body. An ore pass is driven on one side of the drift, and the ore pass leads directly to the lowest stage haulage roadway; a ramp is driven downward from the stope access roadway of the sublevel to the stage haulage roadway, and a ramp is driven upward to the stage haulage roadway of the upper stage;

[0010] A plurality of ore drawing roadways are driven from the drift along the direction perpendicular to the strike direction a of the ore body corresponding to each ore room to a predetermined position on the footwall of the ore body, and the ore drawing roadways are connected to form a trench ore receiving roadway.

[0011] An ore room access roadway is opened along the strike direction a at the center position of the interval crown pillar. From the position corresponding to the center line of the panel pillar of its lower panel in the drift, a downwardly inclined panel access roadway is driven to vertically connect to the ore room access roadway; a roof cutting space is opened in the middle of the ore room. As the roof cutting space is opened, roof support bolts and cables are used to reinforce the roof support layer.

[0012] S3. In the trench ore receiving roadway, fan-shaped blast holes are drilled with the cut as the free face, and taking the cut as the free space, the blasting is completed in several times to form a draw and ore receiving space.

[0013] S4. The "one extraction and one stop" method is adopted for mining, and the ore body within the stage is mined from bottom to top.

[0014] S5. The ore drawing roadways and the roof cutting raise are blocked, and then the ore room is backfilled.

[0015] Furthermore, in step S1, the stage height is controlled within 40m to 60m, the length of a single ore room along the dip direction f of the ore body is 20m to 30m, and the width along the strike direction a of the ore body is controlled within 15m to 20m; the width of the interval crown pillar is 8m to 10m, the length of the panel along the strike direction a of the ore body is 100m to 120m, and the width of the panel pillar is 10m to 15m.

[0016] Furthermore, the interval crown pillar is perpendicular to the roof support layer.

[0017] Further, in step S2, the steps of opening the roof cutting space are as follows: a roof cutting raise is opened in the middle of the ore room, the ore room connection roadways are connected to each roof cutting raise, roof cutting cross headings are driven in both sides of the ore room perpendicular to the roof cutting raise at the interval of the top pillars, with the roof cutting raise as the free face, roof cutting is carried out in the roof cutting cross headings to form the roof cutting space.

[0018] Preferably, in step S2, the length of the stope connection roadway at the bottom of the stage is greater than that of the stope connection roadway at the subsection, and the length ratio is about 8-12:1; the length of the ore drawing roadway along the dip direction b of the ore body is 10m-12m; the predetermined position at the footwall of the ore body is the position where the vertical distance from the trench ore receiving roadway to the footwall boundary of the ore body is 5m-8m; the thickness of the roof protection layer is 1m-2m; the length of the rock bolts and cable bolts in the roof protection bolts and cable bolts is 1.5m-2m, and the length of the cable bolts is 3m-4m.

[0019] Further, in step S3, the method for forming the cutting slot is as follows: a cutting raise is drilled upward at the intersection of an ore drawing roadway and a trench ore receiving roadway in the ore room, and at the intersection of the trench ore receiving roadway and the ore drawing roadway, fan-shaped blast holes are drilled into the ore body, and blasting is carried out with the cutting raise as the free face to form the cutting slot.

[0020] Further, in step S4, the steps of stoping are as follows: in the roof cutting space, downward stoping blast holes are drilled, the powder factor and related blasting parameters are determined according to the throw blasting, the ore is broken and thrown into the trench ore receiving roadway, the ore is shoveled from each ore drawing roadway and poured into the nearby ore pass; the ore body in the ore room is blasted in 3-4 times until the stoping is completed.

[0021] Further, in step S2, the roof cutting raise, the ore room connection roadways, the panel connection roadways, the cross vein haulage roadways, the stope connection roadways and the stage haulage roadways form a common passage for ventilation, personnel access, equipment passage and backfilling, forming a complete ventilation system and multiple safety exits.

[0022] Further, before step S5 for backfilling, filling retaining walls need to be set at the intersection position of the roof cutting raise and the ore room connection roadway and at the corresponding positions at both ends of the ore drawing roadway and the trench ore receiving roadway.

[0023] Further, when backfilling in step S5, the filling body with a cement-sand mass ratio of 1:4 is used for the first-step stope; the filling body with a cement-sand mass ratio of 1:20 or hydraulic filling is used for the second-step stope.

[0024] Beneficial effects:

[0025] This application mentions a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall rock. For gently inclined ore bodies with broken hanging wall rock, this application leaves a roof protection layer on the hanging wall of the ore body and adopts a combined support method of rock bolts and long cable bolts to ensure the stability of the roof protection layer and the hanging wall rock.

[0026] The divided ore rooms are all along the dip direction f of the ore body. On the premise of ensuring the throwing effect, the length of the ore room can be increased, so as to ensure the ore quantity and production capacity of a single ore room. The ore rooms within a stage are mined from bottom to top, and then panels are divided along the strike direction of the ore body. In a panel, the ore rooms in the same sublevel are mined alternately. After the lower sublevel ore rooms are mined and backfilled, the corresponding upper ore rooms can be mined, so that multiple ore rooms in the panel can be mined simultaneously, thus improving the mining intensity and efficiency of gently inclined ore bodies;

[0027] The ore room connecting roadways connect each caving raise. The caving raises, ore room connecting roadways, panel connecting roadways, drift along the vein, stope connecting roadways and stage haulage roadways form a common passage for ventilation, personnel access, equipment passage and backfilling, forming a complete ventilation system and multiple safety exits, saving processes and reducing costs.

[0028] Each stage is divided into 2 sublevels. The ore pass in the middle sublevel is arranged at the intersection of the drift along the vein and the panel connecting roadway in the strike direction. The ore passes in each sublevel lead directly to the stage haulage roadway at the bottommost layer, forming a transportation system composed of stope connecting roadways and stage haulage roadways within the stage, saving the process of opening roadways, improving the mining efficiency, and having a strong ore passing capacity, which can further increase the transportation capacity of gently inclined ore bodies.

[0029] Under the protection of the protective top layer, downward parallel medium-deep holes are drilled in the caving space, and the ore is caved into the trough ore receiving space at the bottom of the sublevel by using the throwing effect, overcoming the problem of stope transportation where gently inclined ore bodies cannot use the self-weight of the ore for chuting, which is also an important measure to improve the mining efficiency of gently inclined ore bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the operation principle diagram of the present invention;

[0031] Figure 2 is Figure 1 the sectional view taken along line I-I in

[0032] Figure 3 is Figure 1 the sectional view taken along line II-II in

[0033] Figure 4 is Figure 1 the sectional view taken along line III-III in

[0034] Figure 5 is Figure 1 the sectional view taken along line IV-IV in

[0035] Figure 6 is the cutting blast hole diagram of the present invention;

[0036] Figure 7 is Figure 6Cross-sectional view A-A in the middle;

[0037] Figure 8 is Figure 6 Cross-sectional view B-B in the middle;

[0038] Explanation of reference numerals in the drawings:

[0039] 1 - Ore body; 2 - Stage haulage roadway; 3 - Stope connection roadway; 4 - Along-strike haulage roadway; 5 - Ore drawing roadway; 6 - Trench ore receiving roadway; 7 - Ramp; 8 - Raise; 9 - Panel connection roadway; 10 - Ore room connection roadway; 11 - Roof cutting raise; 12 - Roof cutting crossheading; 13 - Roof protection layer; 14 - Interval crown pillar; 15 - Roof protection cable bolt; 16 - Roof protection bolts and cable bolts; 17 - Downward stoping blast holes; 18 - Cut-through raise; 19 - Roof cutting space; 20 - Caved ore; 21 - Fan-shaped blast holes; 22 - Panel pillar; 23 - Filling retaining wall; 24 - First-stage stope; 25 - Second-stage stope; 26 - Ore room;

[0040] a represents the strike direction of the ore body, b represents the dip direction of the ore body, c represents the vertical direction of the ore body, d represents the hanging wall direction of the ore body, e represents the footwall direction of the ore body, and f represents the inclination direction of the ore body. Specific implementation manners

[0041] For better explaining the present invention for easy understanding, the present invention will be described in detail below in conjunction with the drawings through specific implementation manners.

[0042] A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall rocks proposed in an embodiment of the present invention. For better understanding the above technical solution, the exemplary embodiments of the present invention will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0043] To achieve the above object, the present invention mentions a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall rocks. The gently inclined medium-thick to thick ore bodies described in the present invention have a relatively gentle dip angle, generally with a dip angle of 11° to 22° and a thickness of 5 m to 15 m. The steps of the mining method include:

[0044] S1. Stope layout: As Figure 1 and Figure 2As shown in the figure, within a stage, 1 to 3 sublevels are arranged along the vertical direction c of the ore body, and multiple panels are divided at a predetermined distance along the strike direction a of the ore body; within the sublevels of the same panel, multiple ore rooms 26 are divided along the strike direction a of the ore body, and the divided ore rooms 26 are all along the dip direction f of the ore body. In this way, on the premise of ensuring the throwing effect, the length of the ore room 26 can be increased, thereby ensuring the ore quantity and production capacity of a single ore room 26. An interval top pillar 14 is arranged between adjacent ore rooms 26 in the vertical direction c of the ore body. The interval top pillar 14 is perpendicular to the protective layer 13, and the protective layer 13 is located in the hanging wall direction d of the ore body 1 of the ore body, that is, the position of the broken hanging wall surrounding rock; panel pillars 22 are left at both ends of the panel along the strike direction a of the ore body. In the same sublevel of the panel, the ore rooms 26 are alternately set as first-step stopes 24 and second-step stopes 25, and the first-step stopes 24 and the second-step stopes 25 are mined in the way of "mining one and leaving one". The ore body within the stage is mined from bottom to top, and the lower ore rooms support the upper ore rooms, that is, the lower ore rooms 26 are mined first, and after backfilling, the upper ore rooms 26 are mined; the first-step stopes 24 are filled with cement. When mining the second step, the filling body of the first-step stope 24 serves as the ore pillar for the second-step mining, creating stable working conditions for the second-step mining.

[0045] The stage described in the present invention is: in the vertical direction c of the ore body, at a certain distance interval, one or several main haulage roadways consistent with the strike direction a of the ore body are driven to divide the ore body into block sections in the vertical direction. This block section is the stage, and the main haulage roadway is the stage haulage roadway 2. The vertical distance between the bottom plates of two adjacent upper and lower stage haulage roadways 2 is the stage height.

[0046] A panel is a mining area horizontally distributed within the stage along the strike direction a of the ore body.

[0047] A sublevel is a mining area that divides the stage into multiple sections along the vertical direction c of the ore body within the stage.

[0048] An ore room 26 is multiple mining areas divided within the panel along the strike direction a of the ore body within the sublevel range. The length of the ore room refers to the length along the dip direction f of the ore body (the dip refers to the inclination angle between the vertical direction of the ore body and the horizontal plane), and the width is the length along the strike direction a of the ore body.

[0049] The stage height should consider the length of a single ore room 26 along the dip direction f of the ore body, and it is appropriate to control it within 40m to 60m. The length of a single ore room 26 along the dip direction f of the ore body is preferably 20m to 30m, and the width along the strike direction a of the ore body is controlled within 15m to 20m; the width of the interval top pillar 14 is 8m to 10m, the length of the panel is the length along the strike direction a of the ore body is 100m to 120m, and the width of the panel pillar 22 is 10m to 15m.

[0050] S2. Development: At the horizontal positions between the bottom of the stage and each sublevel, a stage haulage roadway 2 is opened along the strike direction a of the orebody. At the position corresponding to the centerline of the panel pillar 22 in the panel in the stage haulage roadway 2, a stope access roadway 3 is driven along the direction perpendicular to the strike direction a of the orebody (or along the dip direction b of the orebody). And the length of the stope access roadway 3 at the bottom of the stage is greater than that of the stope access roadway 3 of the sublevel, and the length ratio is about 8 - 12:1, facilitating the ore pass 8 arranged in the upper roadway to directly reach the bottommost stage haulage roadway 2. At a predetermined position in the footwall direction e of the orebody, a drift is driven along the strike direction a of the orebody at the end of the stope access roadway 3. The drift is connected to the stope access roadway 3, and an ore pass 8 is driven on one side of the drift (the side away from the orebody 1). The ore passes 8 of each stage and each sublevel all directly reach the bottommost stage haulage roadway 2, saving the process of roadway opening and improving the mining efficiency; a ramp 7 is driven downward from the stope access roadway 3 of the sublevel to the stage haulage roadway 2, and a ramp 7 is driven upward to the stage haulage roadway 2 of the upper stage to connect each stage and each sublevel.

[0051] As Figure 3 and Figure 4 shown, a plurality of ore drawing roadways 5 are driven from the drift along the direction perpendicular to the strike direction a of the orebody corresponding to each ore room 26 to a predetermined position in the footwall of the orebody 1. 2 - 3 ore drawing roadways 5 are arranged corresponding to each ore room 26. The length of the ore drawing roadway 5 along the dip direction b of the orebody is preferably 10m - 12m, ensuring that the load-haul-dump machine can fully load ore in the ore drawing roadway 5.

[0052] At the stage level, the ore pass 8 is arranged in the middle position of the panel for sharing within one panel; at the sublevel, near the centerline of the panel pillar 22 between each panel, the ore quantity on both sides of the ore pass 8 is basically the same, minimizing the transportation work during the ore transportation process.

[0053] At a predetermined position in the footwall direction e of the orebody, a slot drawpoint drift 6 is formed by connecting all the ore drawing roadways 5 along the strike direction a of the orebody; the vertical distance between the slot drawpoint drift 6 and the footwall boundary of the orebody 1 is controlled within 5m - 8m to ensure that the undercut ore drawing space can accommodate the ore quantity of each blast.

[0054] As Figure 1 and Figure 2 shown, a crosscut between ore rooms 10 is opened along the strike direction a at the center position of the interval crown pillar 14. From the drifts at the stage level and the sublevel corresponding to the centerline position of the panel pillar 22 in the lower panel, a downwardly inclined panel crosscut 9 is driven to be perpendicular to the crosscut between ore rooms 10, and the panel crosscut 9 is connected to the crosscut between ore rooms 10. The panel crosscut 9 is the access to each ore room, and then the crosscut between ore rooms 10 is used to connect the ore rooms along the strike, facilitating the access of workers, materials, equipment, and ventilation.

[0055] As Figure 2 shown, a roof-cutting rise 11 is opened in the middle of each ore room 26 in the panel area. The ore room connecting roadway 10 connects each roof-cutting rise 11. The roof-cutting rise 11, the ore room connecting roadway 10, the panel connecting roadway 9, the drift along the vein 4, the stope connecting roadway 3 and the stage haulage roadway 2 form a passage for ventilation, personnel access, equipment passage and filling, forming a complete ventilation system and multiple safety exits, saving processes and reducing costs; perpendicular to the roof-cutting rise 11 and towards both sides of the ore room 26 near the spacer sill pillar 14, a roof-cutting crossheading 12 is driven to the left and right ( Figure 2 in the left and right directions in ). The boundary of the ore room 26 is used as a free face, and parallel blast holes are drilled in the roof-cutting crossheading 12 for roof cutting to form a roof-cutting space 19. As the roof-cutting space 19 is opened, towards the hanging wall direction d of the ore body, the protective layer 13 is reinforced by the combined support method of roof-bolting and cable bolting 16. The bolt is a resin bolt with full-length anchorage and a length of 1.5 m to 2 m, and the cable bolt has a length of 3 m to 4 m. By pre-supporting the protective layer 13, a relatively stable working space is created during the ore body mining process, avoiding accidents caused by the caving of the hanging wall surrounding rock and the dilution of the ore caused by the mixing into the ore.

[0056] The roof-cutting rise 11 is parallel to the hanging wall boundary of the ore body 1, which is convenient for construction, avoids over-excavation on the hanging wall, exposes the hanging wall surrounding rock, and affects the stability of the roof-cutting space; and a protective layer 13 with a thickness of 1 m to 2 m is left between the roof of the roof-cutting rise 11 and the hanging wall boundary of the ore body 1.

[0057] S3. Cutting: As Figure 6 and Figure 7 shown, a cutting raise 18 is drilled upward at the ore-drawing roadway 5 and the trough ore-drawing roadway 6 in the ore room 26. At the intersection of the trough ore-drawing roadway 6 and the ore-drawing roadway 5, fan-shaped blast holes 21 are drilled towards the ore body 1, and a cutting slot is formed by blasting with the cutting raise 18 as the free face; as Figure 8 shown, then in the trough ore-drawing roadway 6, fan-shaped blast holes 21 are drilled with the cutting slot as the free face, and with the cutting slot as the free space, the blasting is completed in 2 - 3 times to form a draw-off ore-loading space;

[0058] Specifically, as Figure 6 shown, the cutting raise 18 is rectangular, with a length of 2.5 m and a width of 1.5 m to 1.8 m, and the long side is arranged along the ore body strike direction a. As Figure 7 and Figure 8As shown in the figure, the burden of the cut fan-shaped blast holes 21 is controlled within 1.3 m to 1.5 m, and the hole bottom distance is controlled within 1.5 m to 2 m; the fan-shaped blast holes 21 between the cut raise 18 and the ore-drawing roadway 5 are blasted in the same sub-section. In the figure, ①-⑧ represent the section numbers of the blast holes at the corresponding positions. The first blast hole in each row near the cut raise 18 is the first section ①, and then the second blast hole adjacent to it is the second section ②, and so on. The detonator interval time between adjacent sections is 50 ms; after blasting, ore is drawn from the ore-drawing roadway 5 corresponding to the cut raise 18. After the ore drawing is completed, the fan-shaped blast holes 21 on the left and right sides of the cut raise 18 are then blasted. Four rows of blast holes are blasted at a time. The first row of blast holes on the left and right sides of the cut raise 18 is the first section, and so on. The detonator delay interval time between rows is 50 ms. There is no delay interval between the blast holes on the same row surface, that is, they are detonators of the same section. After each blasting, ore is drawn until the ore drawing is completed after all the blast holes are blasted, forming a undercut ore-drawing space.

[0059] S4. Stoping: The first-stage stope 24 and the second-stage stope 25 are mined in the way of "mining every other one"; as Figure 1 and Figure 5 shown in the figure, in the caving space 19, downward stoping blast holes 17 are drilled. According to the throw blasting to determine the specific charge of explosives and related blasting parameters, the ore is broken and thrown into the trench ore-drawing roadway 6, overcoming the problem of stope transportation where the gently inclined ore body cannot use the self-weight of the ore for chuting; Ore is shoveled from each ore-drawing roadway 5 and poured into the nearby ore pass 8; The ore body in the ore chamber 26 is blasted in 3 to 4 times until the stoping is completed;

[0060] Before undercutting, the parallel blast holes and the cut blast holes are completed simultaneously. Drill holes in the direction opposite to the dip direction f of the ore body, that is, drill rock from the bottom of the ore chamber 26 upwards; When charging, workers should operate with safety ropes. Before cutting and stoping, barrier doors are installed in the access between the lower crosscut and the interval crown pillar 14 to prevent the thrown ore from collapsing into the ore chamber connecting roadway 10 in the interval crown pillar 14.

[0061] The aperture of the parallel blast holes is D, mm; it is determined according to the empirical formula D = (1 / 50 - 1 / 180)H; H is the vertical thickness, m, of the ore 20 that needs to be caved for the caving thickness; When the joints are developed and the strength is low, take the larger value, and vice versa; To control the impact on the protective layer 13 after blasting, stemming is set during charging of the blast holes. The stemming length of the blast holes is calculated according to the empirical formula L S = (20 - 25)D, m; At the same time, a overdrill of 1 m to 2 m is set when drilling the blast holes. The resistance line B is determined according to the empirical formula and the requirements of throw blasting, that is, B = (1.0 - 1.2)L S , m, that is, throw blasting is adopted; When the ore density is large and the strength is high, take the smaller value. The blast hole spacing S = 1.15B, m; The number of rows blasted each time is determined according to the size of the undercut ore-drawing space formed. The volume of the broken and swollen ore body after a single blasting should be less than the volume of the undercut ore-drawing space.

[0062] S5. Filling: Seal the ore-drawing roadway 5 and the roof-cutting rise 11, and then fill the ore chamber 26. According to the "mining every other one" division in step S4, the first-step stope 24 uses a filling body with a cement-sand ratio of 1:4; the second-step stope 25 uses a filling body with a cement-sand ratio of 1:20 or hydraulic filling to reduce the overall filling cost;

[0063] Before filling, filling retaining walls 23 shall be set at the intersection of the roof-cutting rise 11 and the ore chamber connection roadway 10 in the ore body below, and at the corresponding positions at both ends of the ore-drawing roadway 5 and the trench ore-drawing roadway 6 to prevent slurry leakage during the filling of the ore chamber; The filling pipeline is arranged from the panel connection roadway 9 and enters the ore chamber connection roadway 10, and the corresponding ore chamber 26 is filled in the ore chamber connection roadway 10 and the roof-cutting rise 11.

[0064] In summary, a mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall rock proposed by the present invention is applicable to gently inclined medium-thick to thick ore bodies with broken hanging wall rock, improving the mining economy, efficiency and safety, and is suitable for popularization.

[0065] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock, characterized in that The steps are as follows: S1. In one stage, arrange multiple sublevels along the vertical direction (c) of the ore body, and divide multiple panels along the strike direction (a) of the ore body; set multiple ore rooms (26) along the strike direction (a) within the sublevels of the same panel; set interval crown pillars (14) between adjacent ore rooms (26) along the vertical direction (c) of the ore body, and leave panel pillars (22) at both ends of the panel along the strike direction (a) of the ore body; S2. Between the bottom of the stage and each sublevel, open stage haulage roadways (2) along the strike direction (a) of the ore body. At the position corresponding to the center line of the panel pillar (22) in the stage haulage roadway (2), after driving the stope access roadway (3), drive the drift along the strike direction (a) of the ore body. Drive an ore pass (8) on one side of the drift. The ore pass (8) leads directly to the bottommost stage haulage roadway (2); drive a ramp (7) downward from the stope access roadway (3) of the sublevel to the stage haulage roadway (2), and drive a ramp (7) upward to the stage haulage roadway (2) of the upper stage; Drive multiple ore-drawing roadways (5) from the drift along the direction perpendicular to the strike direction (a) of the ore body corresponding to each ore room (26) to the predetermined position on the footwall of the ore body (1), and connect the ore-drawing roadways (5) to form a trough receiving roadway (6); Open a crosscut between ore rooms (10) at the central position of the interval crown pillar (14) along the strike direction (a) of the ore body. From the position corresponding to the center line of the panel pillar (22) of the lower panel in the drift, drive a downward-inclined panel crosscut (9) to vertically connect to the crosscut between ore rooms (10); drive a crown-cut raise (11) in the middle of the ore room (26). The crosscut between ore rooms (10) connects each crown-cut raise (11). At the interval crown pillar (14), drive crown-cut crossheadings (12) perpendicular to the crown-cut raise (11) in both directions of the ore room (26). Using the crown-cut raise (11) as the free face, perform crown-cutting in the crown-cut crossheading (12) to form a crown-cut space (19); leave a protective layer (13) between the roof of the crown-cut raise (11) and the upper boundary of the ore body (1). As the crown-cut space (19) is opened, reinforce the protective layer (13) with roof bolts and cables (16); S3. In the trough receiving roadway (6), drill fan-shaped blast holes (21) using the cut as the free face, and use the cut as the free space to complete blasting in batches to form a draw-in receiving space; S4. Adopt the method of "mining every other one". The ore body within the stage is mined from bottom to top. In the crown-cut space (19), drill downward stoping blast holes (17), and determine the powder factor and related blasting parameters according to throw blasting; S5. Seal the ore-drawing roadway (5) and the crown-cut raise (11), and then backfill the ore room (26).

2. The mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, In step S1, the stage height is controlled at 40 m to 60 m, the length of a single ore chamber (26) along the dip direction (f) of the ore body is 20 m to 30 m, and the width along the strike direction (a) of the ore body is controlled at 15 m to 20 m; the width of the interval crown pillar (14) is 8 m to 10 m, the length of the panel is the length along the strike direction (a) of the ore body, which is 100 m to 120 m, and the width of the panel pillar (22) is 10 m to 15 m.

3. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that The interval crown pillar (14) is perpendicular to the protective layer (13).

4. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, In step S2, the length of the stope connection roadway (3) at the bottom of the stage is greater than that of the stope connection roadway (3) at the sectional position, and the length ratio is 8 - 12:1; the length of the ore-drawing roadway (5) along the dip direction (b) of the ore body is 10 m to 12 m; the predetermined position on the footwall of the ore body (1) is the position where the trench ore-drawing roadway (6) is 5 m to 8 m vertically away from the footwall boundary of the ore body (1); the thickness of the protective layer (13) is 1 m to 2 m; among the protective roof bolts and cables (16), the length of the bolts is 1.5 m to 2 m, and the length of the cables is 3 m to 4 m.

5. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, In step S3, the method for forming the cut is as follows: a cut raise (18) is drilled upward at the intersection of an ore-drawing roadway (5) and a trench ore-drawing roadway (6) in the ore chamber (26), and at the intersection of the trench ore-drawing roadway (6) and the ore-drawing roadway (5), fan-shaped blast holes (21) are drilled into the ore body (1), and the cut is formed by blasting with the cut raise (18) as the free face.

6. The mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, In step S4, the stoping steps are as follows: in the roof-cutting space (19), downward stoping blast holes (17) are drilled, the powder factor and related blasting parameters are determined according to the throw blasting, the ore is broken and thrown into the trench ore-drawing roadway (6), the ore is shoveled from each ore-drawing roadway (5) and poured into the nearby ore pass (8); the ore body in the ore chamber (26) is blasted in 3 to 4 times until the stoping is completed.

7. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, In step S2, the roof-cutting raise (11), the ore chamber connection roadway (10), the panel connection roadway (9), the drift along the vein (4), the stope connection roadway (3) and the stage haulage roadway (2) form a common passage for ventilation, personnel access, equipment passage and filling, forming a complete ventilation system and multiple safety exits.

8. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that, Before step S5 for filling, filling retaining walls (23) need to be set at the intersection position of the roof-cutting raise (11) and the ore chamber connection roadway (10) and at the corresponding outlet positions at both ends of the ore-drawing roadway (5) and the trench ore-drawing roadway (6).

9. A mining method for gently inclined medium-thick to thick ore bodies with broken hanging wall surrounding rock according to claim 1, characterized in that When filling in step S5, a filling body with a cement-sand mass ratio of 1:4 is used for the first-step stope (24); a filling body with a cement-sand mass ratio of 1:20 or hydraulic sand filling is used for the second-step stope (25).

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