Mining method of pre-controlled top and directional throwing of ore in inclined medium-thick ore body

Abstract

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, which belongs to the field of mining technology. The method divides the mining area into multiple sections, and each section is connected by a ramp, a ramp connecting road, a segmented vein tunnel, a ore-exiting vein tunnel, and a cutting tunnel; each section uses a shallow hole to cut the top of the ore body to form a stepped top cutting layer, ensuring that the bottom plate of the top cutting layer is a horizontal bottom plate, and the mining area roof is supported by anchor rods and metal mesh in the top cutting layer, realizing full anchor mesh support for the top cutting layer. A medium-deep hole rock drill is used to drill downward ore-dropping blastholes and throwing blastholes in the top cutting layer, and medium-deep hole blasting is carried out. The collapsed ore is thrown into the lower mining project through the throwing blasthole to realize throwing and dropping of ore. During the mining process, a certain combination of ore pillars is reserved to effectively support the roof. The method can realize the mining of inclined medium-thick ore bodies safely and efficiently.

Description

Technical Field

[0001] The invention relates to the technical field of mining, 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 ore body dip angle, the collapsed ore cannot be discharged by gravity. At the same time, mechanized equipment operates on the inclined working surface, making construction difficult.

[0003] The current conventional mining method is the room-and-pillar method, which uses shallow-hole mining. An uphill mining system is deployed at the bottom of the ore body within the stope, with the uphill mining system serving as the free surface for layered mining. Electric rakes are used to transport some of the collapsed ore out of the stope, leaving the remaining ore as a platform for the next layer of ore. Workers then carry out mining operations on the collapsed ore, recovering the upper ore body until the ore body roof is reached and ore is placed in a centralized manner. This process has low production efficiency, high labor intensity, and high operational safety risks. Another shallow-hole mining method is to deploy an uphill mining system at the upper part of the ore body along the hanging wall boundary, with the uphill mining system serving as the free surface for mining. After the top layer of mining is completed, the roof is supported with anchors and metal mesh, and then bottom mining is carried out on the lower ore. Each time the collapsed ore is completely removed, the entire stope is mined. This process can effectively support the roof, but bottom mining is difficult, and as mining progresses, the height of the two sides of the stope increases, increasing operational risks within the stope.

[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-entry segmented open-pit mining method for inclined medium-thick ore bodies. By arranging two rock drilling approaches and medium-deep holes in the ore body, the two rock drilling approaches retreat at the same time to avoid personnel entering the mining area to carry out operations. However, this process is only applicable to situations where the upper wall surrounding rock of the ore body is relatively stable. For ore bodies with poor upper wall surrounding rock stability, the upper wall 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 with 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 roof with anchor rods and metal mesh in the top cutting layer. Downward medium-deep holes are arranged in the top cutting layer, and explosive transportation is used to throw the collapsed ore into the ore discharge funnel. This technology adopts a 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, the mining field has no pillar support. When the ore body stability is poor, as the exposed area of the mining field increases, its roof is very likely to collapse.

[0005] In view of this, it is necessary to design a mining method for pre-controlled 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 pre-controlling the top and directional throwing of ore in an inclined medium-thick ore body, wherein the mining field is divided into multiple sections, and each section is connected by a ramp, a ramp connecting road, a segmented vein tunnel, a ore-discharging vein, and a cutting tunnel; each section uses a shallow hole to perform a top cutting operation on 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 to ensure that the bottom plate of the cutting top layer is a horizontal bottom plate, and the mining field roof is supported by anchor rods and metal mesh in the cutting top layer to realize full anchor mesh support of the cutting top layer; 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-discharging project through the throwing blasthole, thereby realizing throwing ore.

[0007] The present invention reserves a certain number of combined pillars during the mining process, based on the exposed area of the stope, to effectively support the roof. This technology can solve the technical problem of safely and efficiently mining inclined medium-thick ore bodies in metal mines. This method can safely and efficiently mine inclined medium-thick ore bodies.

[0008] To achieve the above-mentioned object, 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:

[0009] S1: excavating a ramp in the footwall of the ore body to be mined, excavating ramp connecting roads in the direction of the ore body at intervals of 10-15 m in the vertical direction of the ramp, excavating segmented vein-following roadways in the direction of the ore body at the junction of the ramp connecting roadways and the ore body, and simultaneously excavating cutting roadways in the footwall of the ore body to divide the mining area into different segments; excavating the cutting roadways in the segmented vein-following roadways at intervals of 5-7 m to exit the ore and penetrate the vein; and excavating the ramp connecting roads horizontally into the surrounding rock of the hanging wall of the ore body;

[0010] S2, in each segmented cutting roadway, excavating a stope connection road in an obliquely upward direction to the boundary of the stope's hanging wall surrounding rock, serving as a passage to the upper part of the stope, and excavating an intra-vein connection road in the stope's connection road near the boundary of the ore body's hanging wall along the strike direction of the ore body. Simultaneously, in the ore body at both ends of the stope, excavating uphill along the ore body's dip direction near the ore body's hanging wall surrounding rock, and excavating a cutting shaft vertically upward at the intersection of the cutting roadway and the uphill on one side of the stope;

[0011] S3, using the uphill as compensation space, the upper part of the stope is cut by shallow hole ore dropping to form a stepped trapezoidal top layer, and the stope roof is supported within the trapezoidal top layer by anchor rods and metal mesh; the length of the anchor rods is 2-2.5m; the spacing and row spacing between adjacent anchor rods are both 0.8-1m; during the top cutting process, point columns are reserved in the stope to support the roof according to the size of the exposed area of the stope; the point columns are spaced 7-10m apart;

[0012] S4, arranging upward parallel medium-length holes in the cutting tunnel, and blasting the cutting shaft as a compensation space to form a cutting groove, which serves as a compensation space for ore recovery;

[0013] S5, using a downward drilling rig to drill downward mining blastholes in the trapezoidal cutting layer, and using micro-delay blasting to collapse and throw the ore into the bottom cutting tunnel; the mining blastholes include drop blastholes and throw blastholes; two rows of blastholes are blasted each time, with one row of drop blastholes and one row of throw blastholes, the drop blastholes are spaced 1.4-1.6m apart, and the resistance line is 1.2-1.4m; the throw blastholes have a resistance line of 1m and a hole spacing of 1-1.2m; the drop blastholes and throw blastholes are detonated in the same row and segment, with a micro-delay interval of 50ms;

[0014] S6, when mining the ore in a medium-long hole, an upper point pillar is reserved in the trapezoidal top layer, and a strip pillar twice the length of the upper point pillar is reserved in the lower ore body to form a "convex" combined pillar with the upper point pillar to support the stope roof;

[0015] S7, using a scraper to collect ore from the ore-extracting vein. After all the ore from this blasting is removed, steps S5-S6 are repeated from bottom to top along the ore body's inclination direction until the entire segmented ore body is mined.

[0016] S8, repeating steps S3-S7, mining in sections from top to bottom until the mining of the entire stope ore body is completed.

[0017] 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 collapsed from the ore-dropping 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.

[0018] As a further improvement of the present invention, in step S3, the trapezoidal cut top layer is drilled with a YT-28 drilling rig to drill a cut top blast hole, and is formed by blasting the cut top blast hole. The bottom plate of the trapezoidal cut top layer is a horizontal bottom plate; the lowest point of each height of the trapezoidal cut top layer is not less than 2m, and the highest point is not higher than 5m; the scraper enters the cut top layer through the mining field connecting road, shovels the ore blasted from the cut top layer and pours it into the cutting shaft; after each cut top layer is formed, the top plate of the corresponding area is supported by anchor rods and metal mesh.

[0019] 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 from the medium and deep holes, forming a "convex" 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.

[0020] The "convex" combination pillar can more effectively support the roof, while avoiding the phenomenon of serious damage caused by excessive roof pressure when the height of a single point pillar is too high. The combination pillar can be reinforced according to the stability of the ore body to enhance the pressure bearing capacity of the pillar.

[0021] 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 wall 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.

[0022] 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.

[0023] As a further improvement of the present invention, in step S2, two uphill rails are arranged, one at each end of the stope.

[0024] 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 stope 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.

[0025] 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.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention provides a mining method for pre-controlling the top of an inclined medium-thick ore body with directional throwing and dropping ore. The method performs comprehensive mechanized mining on the inclined medium-thick ore body by developing a ramp. Shallow holes are used to cut the top of the upper part, and the width of each layer of top cutting is determined according to the height of the empty top. Finally, a trapezoidal cutting top layer with the bottom plate level is formed. The top plate surrounding rock is supported by anchor rods and metal mesh in the cutting top 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 drop blasting holes and throwing blasting holes. By detonating the encrypted throwing blastholes, the ore collapsed 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 scraper is used to carry out ore in the ore vein, ensuring operation safety and ore discharge efficiency; at the same time, when cutting the top and mining, the strip pillars are cut into "convex"-shaped combined pillars according to the stability of the ore rock. This not only overcomes the phenomenon that 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.

[0028] 2. The technical solution of the present invention adopts 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 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

[0029] 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 and dropping the ore.

[0030] Figure 2 for Figure 1 Schematic diagram of the cross section in the II-II direction.

[0031] Figure 3 for Figure 1 Schematic diagram of the cross section in the III-III direction.

[0032] Figure 4 for Figure 1 Schematic diagram of the cross section along the IV-IV direction.

[0033] Figure 5 This is a schematic cross-sectional view of the combined pillar.

[0034] Figure 6 This is a top view schematic diagram of the combined pillar.

[0035] Figure 7 Schematic diagram of the arrangement of mining blastholes.

[0036] Explanation of the accompanying symbols: 1-vein transport tunnel in this stage; 2-vein connecting tunnel; 3-uphill; 4-top cutting blasthole; 5-electric rake chamber; 6-mining 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 outgoing through the 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

[0037] In order to make the objectives, 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.

[0038] It should also be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0039] 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 includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0040] 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.

[0041] 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:

[0042] S1. Arrange a ramp 16 at the foot of the ore body to be mined, excavate ramp connecting roads 17 in the direction of the ore body at a certain height interval (10-15m) in the ramp 16, excavate segmented vein tunnels 19 along the direction of the ore body at the junction of the ramp connecting road 17 and the ore body, and simultaneously excavate cutting tunnels 12 at the foot of the ore body to divide the mining area into different sections; excavate ore-exiting veins 11 in the segmented vein tunnels 19 toward the cutting tunnel 12 at a certain distance (5-7m); arrange an ore chute 18 in the foot of the ore body to serve as a storage and ore-exit channel for the entire mining area.

[0043] Specifically, 3-meter-high intermediate pillars 13 are reserved on both sides of the stope to be mined, and 3-meter-high top pillars 14 are reserved at the top of each segment; the segment height of the stope is 15 meters.

[0044] Cutting tunnel 12 is located at the junction of the ore body and the surrounding rock in the footwall, running along the strike direction of the ore body. A ramp connecting road 17 is driven horizontally into the surrounding rock in the hanging wall of the ore body to further determine the ore body thickness. The intersection of the ore-exiting vein 11 and the cutting tunnel 12 is expanded into a trumpet-shaped top to achieve better ore collection.

[0045] S2, in each segmented cutting tunnel 12, excavate the mining field connecting tunnel 8 in an obliquely upward direction to the boundary of the mining field upper wall surrounding rock as a passage to enter the upper part of the mining field, and excavate the intra-vein connecting tunnel 2 in the mining field connecting tunnel 8 near the boundary of the ore body upper wall along the strike direction of the ore body. At the same time, inside the ore body at both ends of the mining field, near the ore body upper wall surrounding rock, 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.

[0046] Specifically, two uphill gangways 3 are arranged, one at each end of the stope.

[0047] The cutting shaft 15 is arranged on one side of the stope, and its height is determined according to the actual thickness of the ore body.

[0048] In S3, the upper portion of the stope is cut using shallow hole ore drop, using the upper hill 3 as compensation space. This creates a stepped, trapezoidal top layer 7. Within this layer 7, the stope roof is supported using anchor rods 21 and metal mesh. The anchor rods are 2-2.5 meters long, and the spacing between adjacent anchor rods and rows is 0.8-1 meter. During the roof cutting process, a number of point posts are reserved within the stope to support the roof, depending on the size of the exposed area. The spacing between adjacent point posts is 7-10 meters.

[0049] Specifically, the trapezoidal top layer 7 is formed by blasting the top blasthole 4 using a YT-28 drilling rig. The height of the trapezoidal top layer 7 is determined by the effective height of the medium- and long-hole drilling rig. Generally, the height of each layer of the top layer 7 is no less than 2 meters at its lowest point and no more than 5 meters at its highest point. The bottom plate of the top layer 7 is horizontal.

[0050] 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 roof of the corresponding area is supported by anchor rods 21 with metal mesh.

[0051] S4, arranging upward parallel medium-length holes in the cutting tunnel 12, and blasting the cutting shaft 15 as the compensation space to form a cutting groove 20, which serves as the compensation space for ore recovery;

[0052] S5, a downward mining blasthole 6 is drilled in the trapezoidal cutting top layer 7 by a downward drilling rig, and the ore is collapsed and thrown into the bottom cutting tunnel 12 by micro-difference blasting.

[0053] Specifically, the mining blastholes 6 are divided into drop blastholes 601 and cast blastholes 602, with two rows of mining blastholes 6 per blast. The drop blastholes 601 and cast blastholes 602 are arranged in one row each. The drop blastholes 601 are spaced 1.4 to 1.6 meters apart, with a resistance line of 1.2 to 1.4 meters. The cast blastholes 602 have a resistance line of 1 meter and a spacing of 1 to 1.2 meters. The drop blastholes 601 and cast blastholes 602 are detonated in the same row and segment, with a micro-difference interval of 50 milliseconds.

[0054] S6, when the ore is dropped from the medium-deep hole, 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 with a length twice that 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.

[0055] Specifically, the combined pillar 10 is divided into two sections: an upper point pillar 102, formed during the top cutting process, with a cross-sectional dimension of 3m x 3m. A lower strip pillar 101, formed during the ore dropping process in the medium- to deep-hole, has a cross-sectional dimension of 6m x 3m. Together, they form a "convex" combined pillar 10. A row of combined pillars 10 is reserved within each section, with three to four groups of combined pillars 10. The distance between adjacent combined pillars 10 is 7-10m.

[0056] The "convex" type combined 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 is seriously damaged due to excessive roof pressure.

[0057] The combined pillar 10 can be reinforced according to the stability of the ore body to enhance the pressure bearing capacity of the pillar.

[0058] S7, the ore is collected and discharged by means of a scraper 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.

[0059] Specifically, the ore collapsed from the blasthole 601 is forced to be thrown into the receiving project formed by the cutting tunnel 12 and the ore vein 11 through the blasting of the throwing blasthole 602, and is shoveled by the shovel loader in the ore vein 11, transported out and poured into the ore chute 18.

[0060] S8, repeating steps S3 to S7, mining in sections from top to bottom until the mining of the entire stope ore body is completed.

[0061] The mining method of pre-controlled top directional throwing and dropping of inclined medium-thick ore bodies in this application is suitable for ore body inclination angles of 30° to 45° and ore body thickness of not less than 4m.

[0062] In the embodiment of the present application, the distance between each ore-producing vein 11 is 5-7 meters, and the dimensions of the ore-producing vein 11 are (2.4-2.8) meters by (2.4-2.8) meters. The dimensions of the uphill 3 and the cutting shaft 15 are 2 by 2 meters. The dimensions of the ramp connecting road 17, the stope connecting road 8, and the intra-vein connecting road 2 are (2.5-3) meters by (2.5-3) meters. The dimensions of the cutting road 12 are 2.5 meters by 2.5 meters.

[0063] In the embodiment of the present application, the overall mining sequence 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 needs, the top cutting of the next segment can also be carried out simultaneously with the mining process of the upper segment to improve the mining efficiency of the stope.

[0064] A certain enterprise adopted the mining method of pre-controlled top directional throwing of ore in an inclined medium-thick ore body according to this embodiment to mine a certain actual inclined medium-thick ore body. Compared with the room-and-pillar method originally adopted, the production efficiency of the mining site was effectively improved, the safety of the mining site operation was guaranteed, and better economic and safety benefits were brought to the enterprise.

[0065] In summary, the present invention provides a mining method for pre-controlling the top of an inclined medium-thick ore body with directional throwing and dropping of ore, which conducts comprehensive mechanized mining of the inclined medium-thick ore body by ramp development, cuts the top with shallow holes at the top, and determines the width of each layered top cut according to the height of the empty top, finally forming a trapezoidal cutting top layer with the bottom plate level, and supports the top plate surrounding rock with anchor rods and metal mesh in the cutting top layer, so as to realize the top plate protection work in advance; the lower ore body is drilled with a downward medium-deep hole trolley, and micro-difference blasting is carried out by combining blast holes and throwing blast holes. The ore from the collapsed blastholes is thrown into the receiving project through the detonation of the densely packed throwing blastholes, thus realizing the throwing of ore from the inclined medium-thick ore body; in each section, a scraper is used to carry out ore discharge in the ore-discharging vein, thus ensuring the safety of the operation and the efficiency of ore discharge; at the same time, when cutting the top and mining 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 the excessive roof pressure when the height is too high, but also avoids the problem of excessive ore loss rate caused by reserved strip pillars.

[0066] 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 safety is good. Through the above technical solution, safe and efficient mining of inclined medium-thick ore bodies can be finally achieved, and the overall safety management level of the enterprise can be improved.

[0067] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A mining method for pre-controlling the top of a medium-thick ore body with directional throwing and dropping, characterized in that: The following steps are involved: S1: excavating a ramp in the footwall of the ore body to be mined, excavating ramp connecting roads in the direction of the ore body at intervals of 10-15 m in the vertical direction of the ramp, excavating segmented vein-following roadways in the direction of the ore body at the junction of the ramp connecting roadways and the ore body, and simultaneously excavating cutting roadways in the footwall of the ore body to divide the mining area into different segments; excavating the cutting roadways in the segmented vein-following roadways at intervals of 5-7 m to exit the ore and penetrate the vein; and excavating the ramp connecting roads horizontally into the surrounding rock of the hanging wall of the ore body; S2, in each segmented cutting roadway, excavating a stope connection road in an obliquely upward direction to the boundary of the stope's hanging wall surrounding rock, serving as a passage to the upper part of the stope, and excavating an intra-vein connection road in the stope's connection road near the boundary of the ore body's hanging wall along the strike direction of the ore body. Simultaneously, in the ore body at both ends of the stope, excavating uphill along the ore body's dip direction near the ore body's hanging wall surrounding rock, and excavating a cutting shaft vertically upward at the intersection of the cutting roadway and the uphill on one side of the stope; S3, using the uphill as compensation space, the upper part of the stope is cut by shallow hole ore dropping to form a stepped trapezoidal top layer, and the stope roof is supported within the trapezoidal top layer by anchor rods and metal mesh; the length of the anchor rods is 2-2.5m; the spacing and row spacing between adjacent anchor rods are both 0.8-1m; during the top cutting process, point columns are reserved in the stope to support the roof according to the size of the exposed area of the stope; the point columns are spaced 7-10m apart; S4, arranging upward parallel medium-length holes in the cutting tunnel, and blasting the cutting shaft as a compensation space to form a cutting groove, which serves as a compensation space for ore recovery; S5, using a downward drilling rig to drill downward mining blastholes in the trapezoidal cutting layer, and using micro-delay blasting to collapse and throw the ore into the bottom cutting tunnel; the mining blastholes include drop blastholes and throw blastholes; two rows of blastholes are blasted each time, with one row of drop blastholes and one row of throw blastholes, the drop blastholes are spaced 1.4-1.6m apart, and the resistance line is 1.2-1.4m; the throw blastholes have a resistance line of 1m and a hole spacing of 1-1.2m; the drop blastholes and throw blastholes are detonated in the same row and segment, with a micro-delay interval of 50ms; S6, when mining the ore in a medium-long hole, an upper point pillar is reserved in the trapezoidal top layer, and a strip pillar twice the length of the upper point pillar is reserved in the lower ore body to form a "convex" combined pillar with the upper point pillar to support the stope roof; S7, using a scraper to collect ore from the ore-extracting vein. After all the ore from this blasting is removed, steps S5-S6 are repeated from bottom to top along the ore body's inclination direction until the entire segmented ore body is mined. S8, repeating steps S3-S7, mining in sections from top to bottom until the mining of the entire stope ore body is completed.

2. The mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: An ore chute is arranged at the foot of the ore body; 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 ore-discharging vein through the blasting of the throwing blasthole, and is shoveled in the ore-discharging vein by a scraper, transported out and poured into the ore chute.

3. The mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: In step S3, the trapezoidal cut top layer is formed by blasting the cut top blast holes drilled by a YT-28 drilling rig, and the bottom plate of the trapezoidal cut top layer is a horizontal bottom plate; the lowest point of the trapezoidal cut top layer is not less than 2m, and the highest point is not higher than 5m; the scraper enters the cut top layer through the mining area connecting road, shovels the ore blasted from the cut top layer and pours it into the cutting shaft; after each cut top 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 an inclined medium-thick ore body and directional throwing of ore according to claim 1 is characterized in that: In step S6, the combined pillar is divided into two parts, the upper part being a point pillar with a cross-sectional specification of 3m×3m formed during the top cutting process; the lower part being a strip pillar with a cross-sectional specification of 6m×3m formed when the ore is dropped from the medium-deep hole, forming a "convex" combined pillar.

5. The mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing and dropping ore 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 footwall 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.

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

7. The mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing of ore 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 mining 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; the specifications of the cutting road are 2.5 m×2.5 m.

9. The mining method for pre-controlling the top of an inclined medium-thick ore body and directional throwing of ore 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.

Images