Mining method for inclined medium-thickness ore body pre-controlled roof directional throwing ore breaking

Abstract

The invention provides a mining method for inclined medium-thickness ore body pre-roof-control directional throwing ore breaking, and belongs to the technical field of mine mining. According to the method, a stope is divided into a plurality of sections, and each section is communicated through a slope ramp, a slope ramp connection way, a section along-vein roadway, an ore removal transverse drift and a cutting roadway; performing top cutting operation on the top of the ore body by adopting shallow holes in each section to form a step-shaped top cutting layer, ensuring that a bottom plate of the top cutting layer is a horizontal bottom plate, and supporting a stope top plate in the top cutting layer by adopting anchor rods and a metal net to realize full-anchor-net supporting of the top cutting layer. And drilling downward ore breaking blast holes and throwing blast holes in the top cutting layer by adopting a medium-length hole rock drilling machine, carrying out medium-length hole blasting, and throwing caved ores into the lower ore removal project through the throwing blast holes to realize throwing ore breaking. And a certain combined ore pillar is reserved in the stoping process to effectively support the top plate. According to the method, the inclined medium-thick ore body can be safely and efficiently stoped.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing and dropping ore. Background Art

[0002] The inclined medium-thick ore body has a dip angle between 30° and 55°. Due to the restriction of the dip angle of the ore body, the collapsed ore cannot be released by gravity. At the same time, mechanized equipment operates on the inclined working surface, which makes construction difficult.

[0003] At present, the conventional mining method is the room-pillar method, that is, the shallow hole mining method is adopted. The upper mountain is arranged at the bottom of the ore body in the mining area, and the upper mountain is used as the free surface for layered mining. The electric rake is used to transport part of the collapsed ore out of the mining area, and the remaining ore is used as the platform for the next layer of mining. The personnel carry out the upper ore body recovery operation on the collapsed ore until the top plate of the ore body is recovered and the ore is concentrated. This process has low production efficiency, high labor intensity and high safety risk; another shallow hole recovery method is to arrange the upper mountain along the upper plate boundary on the upper part of the ore body, and the upper mountain is used as the free surface for recovery and mining. After the recovery of the top layer is completed, the top plate is supported by anchor rods and metal mesh, and then the bottom mining operation is carried out for the lower ore. Each time the collapsed ore is completely removed until the recovery of the entire mining area is completed. This process can effectively support the top plate, but the bottom mining operation is difficult, and as the recovery progresses, the height of the two sides of the mining area increases, which increases the operation risk in the mining area.

[0004] With the continuous updating of mining technology, some ore bodies can be mined using medium-deep holes. For example, the invention patent (CN202311562919.5) discloses a dual-access segmented open-pit mining method for inclined medium-thick ore bodies. Two rock drilling approaches are arranged in the ore body, and medium-deep holes are arranged. The two rock drilling approaches retreat at the same time to avoid personnel entering the mining area to work. However, this process is only applicable to situations where the upper surrounding rock of the ore body is relatively stable. For ore bodies with poor upper surrounding rock stability, the upper surrounding rock is very likely to collapse during the mining process, resulting in ore depletion. For ore bodies with poor upper plate stability, the invention patent (CN201610632008.9) discloses a segmented mining method of advanced top cutting and explosive transportation. The method first divides the mining field into strips, cuts the top of the ore body, and supports the top plate with anchor rods and metal mesh in the top cutting layer. Downward medium-deep holes are arranged in the top cutting layer, and the collapsed ore is thrown into the ore discharge funnel by explosive transportation. This technology adopts the medium-deep hole ore dropping method, but the top cutting layer formed by this technology is still an inclined working surface. When the inclination angle of the ore body is large, the rock drilling equipment cannot operate in the mining field. At the same time, there is no pillar support in the mining field. When the stability of the ore body is poor, as the exposed area of ​​the mining field increases, its top plate is very likely to collapse.

[0005] In view of this, it is necessary to design a mining method for pre-controlling the top and directional throwing of ore in inclined medium-thick ore bodies to solve the above problems. Summary of the invention

[0006] The object of the present invention is to provide a mining method for directional throwing and dropping of ore in a pre-controlled top of an inclined medium-thick ore body, wherein a mining field is divided into a plurality of sections, each section being connected by an inclined ramp, an inclined ramp connecting road, a sectioned vein tunnel, a ore-exiting vein tunnel, and a cutting tunnel; each section adopts a shallow hole to carry out a top cutting operation at the top of the ore body, and a stepped cutting top layer is formed according to the height of the top plate through the top cutting operation, so that the bottom plate of the cutting top layer is ensured to be a horizontal bottom plate, and the mining field top plate is supported by anchor rods and metal mesh in the cutting top layer, so that the cutting top layer is fully supported by an anchor mesh; a medium-deep hole rock drill is used to drill downward ore-dropping blastholes and throwing blastholes in the cutting top layer, and medium-deep hole blasting is carried out, and the collapsed ore is thrown into the lower ore-exiting project through the throwing blasthole, so as to realize throwing and dropping of ore.

[0007] The present invention reserves a certain combination of ore pillars to effectively support the roof during the mining process according to the exposed area of ​​the stope. This technology can solve the technical problem of safe and efficient mining of inclined medium-thick ore bodies in metal mines. Through this method, inclined medium-thick ore bodies can be mined safely and efficiently.

[0008] To achieve the above-mentioned purpose, the present invention provides a mining method for pre-controlling the top of a medium-thick ore body and directional throwing and dropping ore, comprising the following steps: S1, excavating a ramp in the lower wall of the ore body to be mined, excavating a ramp connecting road in the direction of the ore body at intervals of 10-15m in the height direction of the ramp, excavating a segmented vein roadway along the direction of the ore body at the junction of the ramp connecting road and the ore body, and excavating a cutting roadway at the lower wall of the ore body to divide the mining site into different sections; excavating a mine-through-veining roadway to the cutting roadway at intervals of 5-7m in the segmented vein roadway; the ramp connecting roadway is excavated horizontally to the surrounding rock of the upper wall of the ore body; S2, in each segmented cutting tunnel, excavate a mining field connecting tunnel in an obliquely upward direction to the boundary of the mining field's upper wall surrounding rock as a passage to enter the upper part of the mining field, and excavate an intra-vein connecting tunnel in the mining field close to the boundary of the upper wall of the ore body along the strike direction of the ore body. At the same time, excavate uphill in the ore body's inclination direction close to the surrounding rock of the upper wall of the ore body inside the ore body at both ends of the mining field, and excavate a cutting shaft vertically upward at the intersection of the cutting tunnel and the upper wall on one side of the mining field; S3, using the upper hill as the compensation space, the upper part of the mining area is cut by shallow hole mining, forming a stepped trapezoidal cutting layer, and the roof of the mining area is supported by anchor rods and metal mesh in the trapezoidal cutting layer; the length of the anchor rods is 2-2.5m; the spacing and row spacing of adjacent anchor rods are 0.8-1m; in the process of cutting the roof, according to the size of the exposed area of ​​the mining area, point columns are reserved in the mining area to support the roof; the spacing of the point columns is 7-10m; S4, arranging upward parallel medium-length holes in the cutting tunnel, and using the cutting shaft as a compensation space to form cutting grooves by blasting, so as to serve as a compensation space for ore recovery; S5, using a downward drilling trolley to drill downward recovery blastholes in the trapezoidal cutting layer, and through micro-difference blasting, the ore is collapsed and thrown into the bottom cutting tunnel; the recovery blastholes include ore-dropping blastholes and throwing blastholes; two rows of blastholes are blasted each time, of which there are one row of ore-dropping blastholes and one row of throwing blastholes, the spacing between the ore-dropping blastholes is 1.4-1.6m, and the resistance line is 1.2-1.4m; the resistance line of the throwing blastholes is 1m, and the hole spacing is 1-1.2m; the ore-dropping blastholes and the throwing blastholes are detonated in the same row and section, and the micro-difference interval time is 50ms; S6, when recovering the ore in the medium-long hole, an upper point column is reserved in the trapezoidal cut layer, and a strip ore column twice the length of the upper point column is reserved in the lower ore body to form a "convex" type combined ore column with the upper point column to support the stope roof; S7, using a scraper to collect ore in the ore-extracting vein, after all the ore from this blasting is removed, repeating steps S5-S6 from bottom to top along the ore body inclination direction until the entire segmented ore body is mined; S8, repeating steps S3-S7, mining one segment at a time from top to bottom until the mining of the entire ore body in the mining area is completed.

[0009] As a further improvement of the present invention, an ore chute is arranged at the lower plate of the ore body to serve as a storage and mining channel for the ore of the entire mining area; the ore that collapses from the ore-falling blasthole is forced to be thrown into the receiving project formed by the cutting tunnel and the mining vein through the blasting of the throwing blasthole, and is shoveled in the mining vein by a shovel loader, transported out and poured into the ore chute.

[0010] As a further improvement of the present invention, in step S3, the trapezoidal cutting top layer is formed by blasting through the cutting top blastholes drilled by a YT-28 drilling rig, and the bottom plate of the trapezoidal cutting top layer is a horizontal bottom plate; the lowest point of the height of each layer of the trapezoidal cutting top layer is not less than 2m, and the highest point is not higher than 5m; the scraper enters the cutting top layer through the mining field connecting road, shovels the ore blasted from the cutting top layer into the cutting shaft; after each cutting top layer is formed, the top plate of the corresponding area is supported by anchor rods and metal mesh.

[0011] As a further improvement of the present invention, in step S6, the combined ore pillars are divided into two parts, the upper ore pillar is a point pillar with a cross-sectional specification of 3m×3m formed in the top cutting process; the lower ore pillar is a strip pillar with a cross-sectional specification of 6m×3m formed when the ore is dropped into the medium and deep holes, forming a "convex" type of combined ore pillar; a row of combined ore pillars is reserved in each segment, the number of the combined ore pillars is 3-4 groups, and the distance between adjacent combined ore pillars is 7-10m.

[0012] The "convex" type combined pillar can support the roof more effectively, and at the same time, avoid the phenomenon that a single point pillar is too high and is seriously damaged due to excessive roof pressure. The combined pillar can be reinforced according to the stability of the ore body to enhance the pressure bearing capacity of the pillar.

[0013] As a further improvement of the present invention, in step S1, the cutting tunnel is arranged at the junction of the ore body and the lower surrounding rock, and is arranged along the strike direction of the ore body; the top of the intersection of the ore-exiting vein and the cutting tunnel is expanded into a trumpet shape to achieve a better ore-receiving effect.

[0014] As a further improvement of the present invention, the inclination angle of the inclined medium-thick ore body to be mined is 30°-45°, the thickness of the ore body is greater than or equal to 4 m, and the height of each segment is 10-15 m.

[0015] As a further improvement of the present invention, in step S2, two uphill roads are arranged, respectively located at two ends of the stope.

[0016] As a further improvement of the present invention, the specifications of the ore-exiting vein are (2.4-2.8) m×(2.4-2.8) m; the specifications of the uphill and cutting shafts are both 2×2 m; the specifications of the ramp connecting road, the mining area connecting road, and the vein connecting road are (2.5-3) m×(2.5-3) m; and the specifications of the cutting tunnel are 2.5 m×2.5 m.

[0017] As a further improvement of the present invention, the top cutting project of the next segment can be carried out simultaneously during the mining process of the upper segment to improve the mining efficiency of the stope.

[0018] The beneficial effects of the present invention are: 1. The present invention provides a mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing and dropping ore. The inclined medium-thick ore body is mined comprehensively and mechanized by ramp development. The upper part is cut with shallow holes, and the width of each layered top cutting is determined according to the height of the empty top, and finally a trapezoidal cutting layer with the bottom plate level is formed. The top plate surrounding rock is supported by anchor rods and metal mesh in the cutting layer, so as to realize the top plate protection work in advance. The lower ore body is drilled by a downward medium-deep hole trolley, and micro-difference blasting is carried out by combining ore dropping blastholes and throwing blastholes. Through the detonation of encrypted throwing blastholes, the ore that falls from the blastholes is thrown into the receiving project, realizing the throwing of ore in the inclined medium-thick ore body; in each section, a shovel loader is used to carry out ore in the ore-carrying vein, ensuring the safety of the operation and the efficiency of ore-carrying; at the same time, when cutting the top and recovering the ore, the strip pillars are cut into "convex"-shaped combined pillars according to the stability of the ore rock, which not only overcomes the phenomenon that the traditional point pillars are severely damaged due to excessive roof pressure when the height is too high, but also avoids the problem of excessive ore loss rate caused by reserved strip pillars.

[0019] 2. The technical solution of the present invention adopts medium-deep holes for recovery blasting under the premise of anchor rods and metal mesh roof protection. The labor intensity of workers is low and the operation safety is good. Through the above-mentioned technical solution, safe and efficient mining of inclined medium-thick ore bodies can be finally achieved, thereby improving the overall safety management level of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the mining method of the present invention for pre-controlling the top of an inclined medium-thick ore body and directional throwing of ore.

[0021] Figure 2 for Figure 1 Schematic diagram of the cross section along the II-II direction.

[0022] Figure 3 for Figure 1 Schematic diagram of the cross section along the III-III direction.

[0023] Figure 4 for Figure 1 Schematic diagram of the cross section along the IV-IV direction.

[0024] Figure 5 This is a schematic cross-sectional view of the combined pillar.

[0025] Figure 6 This is a top view schematic diagram of the combined ore pillar.

[0026] Figure 7 Schematic diagram of the arrangement of blastholes for mining.

[0027] Explanation of the reference numerals: 1-vein transport tunnel in this stage; 2-vein connecting tunnel; 3-uphill; 4-top cutting blasthole; 5-electric rake chamber; 6-recovery blasthole; 601-ore dropping blasthole; 602-throwing blasthole; 7-top cutting; 8-mining connecting tunnel; 9-vein transport tunnel in the upper stage; 10-combined ore pillar; 101-lower strip ore pillar; 102-upper point pillar; 11-ore exit through vein; 12-cutting tunnel; 13-intermediate pillar; 14-top pillar; 15-cutting skylight; 16-ramp; 17-ramp connecting tunnel; 18-ore chute; 19-segmented vein tunnel; 20-cutting groove; 21-anchor rod. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0030] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0031] See also Figures 1 to 7 As shown, for ease of understanding, the figure shows the vein transport tunnel 1 in this stage, the vein transport tunnel 9 in the previous stage and the electric rake chamber 5.

[0032] The present invention provides a mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing and dropping ore, comprising the following steps: S1, a ramp 16 is arranged at the lower wall of the ore body to be mined, and a ramp connecting road 17 is excavated in the direction of the ore body at a certain height interval (10-15m) in the ramp 16, and a segmented vein tunnel 19 is excavated along the direction of the ore body at the junction of the ramp connecting road 17 and the ore body. At the same time, a cutting tunnel 12 is excavated at the lower wall of the ore body to divide the mining area into different sections; an out-of-mine vein 11 is excavated toward the cutting tunnel 12 at a certain distance (5-7m) in the segmented vein tunnel 19; an ore chute 18 is arranged in the lower wall of the ore body to serve as a storage and out-of-mine channel for ore in the entire mining area.

[0033] Specifically, 3-meter-high intermediate pillars 13 are reserved on both sides of the mining area, and 3-meter-high top pillars 14 are reserved at the top of each segment; the segment height of the mining area is 15 meters.

[0034] The cutting tunnel 12 is arranged at the junction of the ore body and the surrounding rock of the lower wall, and is arranged along the strike direction of the ore body. The ramp connecting road 17 needs to be horizontally excavated into the surrounding rock of the upper wall of the ore body to further explore the thickness of the ore body. The top of the intersection of the ore-exiting vein 11 and the cutting tunnel 12 is expanded into a trumpet shape to achieve a better ore receiving effect.

[0035] S2, in each segmented cutting tunnel 12, excavate the mining field connecting road 8 in an oblique upward direction to the boundary of the upper wall surrounding rock of the mining field as a passage to enter the upper part of the mining field, and excavate the intra-vein connecting road 2 in the mining field connecting road 8 near the boundary of the upper wall of the ore body along the direction of the ore body strike, at the same time, inside the ore body at both ends of the mining field, near the upper wall surrounding rock of the ore body, excavate uphill 3 along the inclination direction of the ore body, and excavate a cutting shaft 15 vertically upward at the intersection of the cutting tunnel 12 and the uphill 3 on one side of the mining field.

[0036] Specifically, two uphill gangways 3 are arranged, located at the two ends of the mining area.

[0037] The cutting shaft 15 is arranged on one side of the mining area, and its height is determined according to the actual thickness of the ore body.

[0038] S3, using the upper hill 3 as compensation space, the upper part of the mining area is cut by shallow hole mining, forming a stepped trapezoidal cutting layer 7, and the mining area roof is supported by anchor rods 21 with metal mesh in the trapezoidal cutting layer 7. The length of the anchor rod is 2-2.5m; the spacing and row spacing of adjacent anchor rods are 0.8-1m. During the cutting process, according to the size of the exposed area of ​​the mining area, a certain number of point columns are reserved in the mining area to support the roof. The spacing between adjacent point columns is 7-10m.

[0039] Specifically, the trapezoidal cutting layer 7 is formed by drilling the cutting top blasthole 4 with a YT-28 drilling rig and blasting the cutting top blasthole 4. The height of the trapezoidal cutting layer 7 is determined according to the effective height of the medium-deep hole drilling trolley. Generally, the lowest height of each layer of the cutting top layer 7 is not less than 2m and the highest height is not more than 5m. The bottom plate of the cutting top layer 7 is a horizontal bottom plate.

[0040] The scraper enters the top-cut layer 7 through the stope connection road 8, and the scraper shovels the ore blasted from the top-cut layer 7 and pours it into the cutting shaft 15. After each top-cut layer 7 is formed, the top plate of the corresponding area is supported by anchor rods 21 equipped with metal mesh.

[0041] S4, arranging upward parallel medium-length holes in the cutting tunnel 12, and using the cutting shaft 15 as the compensation space to form a cutting groove 20 by blasting, as the compensation space for ore recovery; S5, a downward recovery blasthole 6 is drilled in the trapezoidal cutting layer 7 by a downward drilling rig, and the ore is collapsed and thrown into the bottom cutting tunnel 12 by micro-difference blasting.

[0042] Specifically, the mining blastholes 6 are divided into blastholes 601 for ore dropping and blastholes 602 for throwing, and two rows of mining blastholes 6 are blasted each time. Among them, there are one row of blastholes 601 for ore dropping and one row of blastholes 602 for throwing. The spacing of blastholes 601 for ore dropping is 1.4-1.6m, and the resistance line is 1.2-1.4m; the resistance line of blastholes 602 for throwing is 1m, and the hole spacing is 1-1.2m. The blastholes 601 for ore dropping and blastholes 602 are detonated in the same row and section, and the micro-difference interval time is 50ms.

[0043] S6, when recovering ore in medium-deep holes, a certain upper point column 102 is reserved in the trapezoidal cutting layer 7 to support the mining area roof, and a lower strip ore column 101 twice the length of the upper point column is reserved in the lower ore body to form a "convex" type combined ore column 10 with the upper point column 102 to support the mining area roof.

[0044] Specifically, the combined pillar 10 is divided into two parts, the upper point pillar 102 is a point pillar with a cross-sectional specification of 3m×3m formed in the process of top cutting, and the lower strip pillar 101 is a strip pillar with a cross-sectional specification of 6m×3m formed when the ore is dropped in the medium-deep hole, forming a "convex" combined pillar 10. A row of combined pillars 10 is reserved in each segment, and the number of combined pillars 10 is 3-4 groups. The distance between adjacent combined pillars 10 is 7-10m.

[0045] The "convex" type combined ore pillar 10 can support the roof more effectively, and at the same time, avoid the phenomenon that when the height of a single type of point pillar is too high, it will be seriously damaged due to excessive roof pressure.

[0046] The combined ore pillar 10 can be reinforced according to the stability of the ore body to enhance the pressure bearing capacity of the ore pillar.

[0047] S7, the ore is collected and discharged by means of a shovel loader in the ore-discharging vein 11. After all the ore from this blasting is discharged, steps S5 to S6 are repeated from bottom to top along the inclination direction of the ore body until the entire segmented ore body is recovered.

[0048] Specifically, the ore that collapses from the blasthole 601 is forced to be thrown into the receiving project formed by the cutting tunnel 12 and the ore-discharging vein 11 through the blasting of the blasthole 602, and is shoveled by a shovel loader in the ore-discharging vein 11, transported out and poured into the ore chute 18.

[0049] S8, repeating steps S3 to S7, mining in sections from top to bottom until the mining of the entire ore body in the mining area is completed.

[0050] The mining method for pre-controlling the top of a medium-thick inclined ore body with directional throwing and dropping of ore in the present application is suitable for an ore body with an inclination angle of 30° to 45° and an ore body thickness of not less than 4m.

[0051] In the embodiment of the present application, the distance between each ore-exiting vein 11 is 5 to 7 m, and the specification of the ore-exiting vein 11 is (2.4 to 2.8) m×(2.4 to 2.8) m. The specifications of the uphill 3 and the cutting shaft 15 are 2×2 m. The specifications of the ramp connecting road 17, the stope connecting road 8, and the intra-vein connecting road 2 are (2.5 to 3) m×(2.5 to 3) m. The specification of the cutting road 12 is 2.5 m×2.5 m.

[0052] In the embodiment of the present application, the overall recovery order of the stope is to proceed from the upper segment to the lower segment. It should be noted that, according to the on-site production requirements, the top cutting of the next segment can also be carried out simultaneously during the recovery process of the upper segment to improve the recovery efficiency of the stope.

[0053] An enterprise adopted the mining method of pre-controlled top directional throwing of ore in an inclined medium-thick ore body of this embodiment to carry out mining of an actual inclined medium-thick ore body. Compared with the room-and-pillar method originally adopted, the production efficiency of the mining field was effectively improved, the safety of the mining field operation was guaranteed, and better economic and safety benefits were brought to the enterprise.

[0054] In summary, the present invention provides a mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing and dropping of ore. The inclined medium-thick ore body is mined comprehensively and mechanized by ramp development. The upper part is cut with shallow holes, and the width of each layered top cutting is determined according to the height of the empty top, and finally a trapezoidal cutting layer with the bottom plate level is formed. The top plate surrounding rock is supported by anchor rods and metal mesh in the cutting layer, so as to realize the top plate protection work in advance. The lower ore body is drilled by a downward medium-deep hole trolley, and micro-difference blasting is carried out by combining ore dropping blast holes and throwing blast holes. The ore falling from the blastholes is thrown into the receiving project through the detonation of encrypted throwing blastholes, realizing the throwing of ore in the inclined medium-thick ore body; in each section, a scraper is used to carry out ore removal in the ore-removing vein, which ensures the safety of operation and the efficiency of ore removal; at the same time, when cutting the top and recovering the ore, the strip pillars are cut into "convex"-shaped combined pillars according to the stability of the ore rock, which not only overcomes the phenomenon that the traditional point pillars are seriously damaged due to excessive roof pressure when the height is too high, but also avoids the problem of excessive ore loss rate caused by reserved strip pillars.

[0055] This technical solution uses medium-deep holes for mining blasting under the premise of anchor rods and metal mesh roof protection. The labor intensity of workers is low and the operation is safe. The above technical solution can eventually achieve safe and efficient mining of inclined medium-thick ore bodies, and improve the overall safety management level of the enterprise.

[0056] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A mining method for pre-controlling the top of a medium-thick ore body and directional throwing of ore, characterized in that: The following steps are involved: S1, excavating a ramp in the lower wall of the ore body to be mined, excavating a ramp connecting road in the direction of the ore body at intervals of 10-15m in the height direction of the ramp, excavating a segmented vein roadway along the direction of the ore body at the junction of the ramp connecting road and the ore body, and excavating a cutting roadway at the lower wall of the ore body to divide the mining site into different sections; excavating a mine-through-veining roadway to the cutting roadway at intervals of 5-7m in the segmented vein roadway; the ramp connecting roadway is excavated horizontally to the surrounding rock of the upper wall of the ore body; S2, in each segmented cutting tunnel, excavate a mining field connecting tunnel in an obliquely upward direction to the boundary of the mining field's upper wall surrounding rock as a passage to enter the upper part of the mining field, and excavate an intra-vein connecting tunnel in the mining field close to the boundary of the upper wall of the ore body along the strike direction of the ore body. At the same time, excavate uphill in the ore body's inclination direction close to the surrounding rock of the upper wall of the ore body inside the ore body at both ends of the mining field, and excavate a cutting shaft vertically upward at the intersection of the cutting tunnel and the upper wall on one side of the mining field; S3, using the upper hill as the compensation space, the upper part of the mining area is cut by shallow hole mining, forming a stepped trapezoidal cutting layer, and the roof of the mining area is supported by anchor rods and metal mesh in the trapezoidal cutting layer; the length of the anchor rods is 2-2.5m; the spacing and row spacing of adjacent anchor rods are 0.8-1m; in the process of cutting the roof, according to the size of the exposed area of ​​the mining area, point columns are reserved in the mining area to support the roof; the spacing of the point columns is 7-10m; S4, arranging upward parallel medium-length holes in the cutting tunnel, and using the cutting shaft as a compensation space to form cutting grooves by blasting, so as to serve as a compensation space for ore recovery; S5, using a downward drilling trolley to drill downward recovery blastholes in the trapezoidal cutting layer, and through micro-difference blasting, the ore is collapsed and thrown into the bottom cutting tunnel; the recovery blastholes include ore-dropping blastholes and throwing blastholes; two rows of blastholes are blasted each time, of which there are one row of ore-dropping blastholes and one row of throwing blastholes, the spacing between the ore-dropping blastholes is 1.4-1.6m, and the resistance line is 1.2-1.4m; the resistance line of the throwing blastholes is 1m, and the hole spacing is 1-1.2m; the ore-dropping blastholes and the throwing blastholes are detonated in the same row and section, and the micro-difference interval time is 50ms; S6, when recovering the ore in the medium-long hole, an upper point column is reserved in the trapezoidal cut layer, and a strip ore column twice the length of the upper point column is reserved in the lower ore body to form a "convex" type combined ore column with the upper point column to support the stope roof; S7, using a scraper to collect ore in the ore-extracting vein, after all the ore from this blasting is removed, repeating steps S5-S6 from bottom to top along the ore body inclination direction until the entire segmented ore body is mined; S8, repeating steps S3-S7, mining one segment at a time from top to bottom until the mining of the entire ore body in the mining area is completed.

2. The mining method for pre-controlling the top of a medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: An ore chute is arranged at the lower plate of the ore body; the ore that collapses from the ore-falling blasthole is forced to be thrown into the receiving mining project formed by the cutting tunnel and the ore-discharging vein through the blasting of the blasthole, and is shoveled by a shovel loader in the ore-discharging vein, transported out and poured into the ore chute.

3. The mining method of pre-controlling the top of the inclined medium-thick ore body and directional throwing and dropping ore according to claim 1 is characterized in that: In step S3, the trapezoidal cutting layer is formed by blasting through the cutting blastholes drilled by a YT-28 drilling rig, and the bottom plate of the trapezoidal cutting layer is a horizontal bottom plate; the lowest point of each height of the trapezoidal cutting layer is not less than 2m, and the highest point is not higher than 5m; the scraper enters the cutting layer through the mining field connecting road, shovels the ore blasted from the cutting layer into the cutting shaft; after each cutting layer is formed, the top plate of the corresponding area is supported by anchor rods and metal mesh.

4. The mining method for pre-controlling the top of a medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: In step S6, the combined ore pillar is divided into two parts, the upper ore pillar is a point pillar with a cross-sectional specification of 3m×3m formed in the top cutting process; the lower ore pillar is a strip pillar with a cross-sectional specification of 6m×3m formed when the ore is dropped in the medium-deep hole, forming a "convex" combined ore pillar.

5. The mining method of pre-controlling the top of a medium-thick ore body and throwing the ore in a directional manner according to claim 1 is characterized in that: In step S1, the cutting tunnel is arranged at the junction of the ore body and the surrounding rock of the lower wall, and is arranged along the strike direction of the ore body; the top of the intersection of the ore-exiting vein and the cutting tunnel is expanded into a trumpet shape.

6. The mining method of pre-controlling the top of a medium-thick ore body and throwing the ore in a directional manner according to claim 1 is characterized in that: The inclined medium-thick ore body to be mined has an inclination of 30°-45° and a thickness of 4 m or more.

7. The mining method of pre-controlling the top of a medium-thick ore body and throwing the ore in a directional manner according to claim 1 is characterized in that: The height of each segment is 10-15 m.

8. The mining method for pre-controlling the top of a medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: The specifications of the ore-exiting vein are (2.4-2.8) m×(2.4-2.8) m; the specifications of the uphill and cutting shafts are both 2×2m; the specifications of the ramp connecting roads, mining area connecting roads, and intra-vein connecting roads are (2.5-3) m×(2.5-3) m; the specifications of the cutting tunnels are 2.5m×2.5m.

9. The mining method of pre-controlling the top of a medium-thick ore body and throwing the ore in a directional manner according to claim 1 is characterized in that: The top cutting work of the next section can be carried out simultaneously during the mining process of the upper section.

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