Flat bottom structure mining method based on fan-shaped hole blasting force-gravity collaborative ore collection

Abstract

The invention belongs to the technical field of mining, and provides a flat-bottom structure mining method based on fan-shaped hole blasting force-gravity collaborative mining, which comprises the following steps: S1, determining a stope arrangement form according to a deep thick and large ore body occurrence form, ground stress conditions, stope sizes and development engineering positions, dividing stopes and determining a target stope; s2, constructing an upper stope linked roadway and a rock drilling roadway from the upper part of the target stope, wherein the upper stope linked roadway is communicated with the rock drilling roadway; constructing a lower stope linked roadway and an ore removal roadway from the lower part of the target stope, wherein the lower stope linked roadway is communicated with the ore removal roadway; the method has the beneficial effects that the depth of the first downward fan-shaped blast hole is gradually reduced from the first cutting groove to the end part of the target stope to form a blasting excavation surface which is inclined to the area of the first cutting groove and is adaptive to the natural repose angle of caved ore rocks, so that caved ores are gathered to an ore removal roadway under the action of gravity and blasting force, the ore removal efficiency of the stope is improved, and the working efficiency of the stope is improved. And the ore removal amount of the remote control carry-scraper is controlled.

Description

Technical Field

[0001] This application belongs to the technical field of mining, and particularly relates to a flat-bottom structure mining method based on the collaborative ore collection of blast force and gravity of fan-shaped holes. Background Art

[0002] The open stoping with subsequent filling mining method has gradually become the mainstream method for the mining of thick and large ore bodies in metal mines in China due to its advantages such as small surface damage, high production efficiency, large resource recovery intensity, and small development and cutting engineering quantity. The bottom structure of the ore chamber mainly adopts a "V"-shaped trench and a "fishbone"-shaped ore-drawing drift for ore drawing, which has problems such as large development and cutting engineering quantity, complex technology, difficult recovery of peach-shaped ore pillars, serious damage to the brow line of the ore-drawing drift, and difficult support; in addition, the ore-drawing roadway in the second-step stope needs to be arranged in the filling body. The filling body itself has low strength, and coupled with the influence of residual ore, it leads to low driving efficiency of the ore-drawing roadway, difficult construction, high construction cost and safety risk, resulting in difficult excavation and support of the ore-drawing roadway in the second-step stope. Although the use of a flat-bottom structure can effectively solve the above problems, since the flat-bottom structure requires a remote-controlled load-haul-dump (LHD) for ore drawing, the ore-drawing efficiency is low and it is difficult to meet the production requirements of the mine; therefore, controlling the ore-drawing volume of the remote-controlled LHD and improving the ore-drawing efficiency of the stope have become the key technical problems in the use of the flat-bottom structure. At the same time, due to the existence of ore-drawing dead corners in the traditional bottom structure and the fact that some caved ores are in a static state during the early ore-drawing stage, for the mining of ore bodies prone to caking, such as the mining of sulfur-bearing deposits, it will cause the ore to cake, resulting in a large amount of residual ore piles accumulated in the stope.

[0003] With the depletion of shallow resources, deep mining has become an important part of China's mining industry. The mining of thick and large ore bodies in deep metal mines is carried out in a special environment of "high stress, high temperature, high humidity and disturbance". When using downward vertical medium-deep holes for rock drilling, the development and cutting engineering quantity of the rock-drilling chamber is large, the exposed area of the chamber roof is large, and it is extremely easy to cause the collapse of the roof of the stope rock-drilling chamber, with the disadvantages of difficult ground pressure control and poor rock-drilling safety, and it is difficult to adapt to deep mining. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0005] To solve the above problems, this application provides a flat-bottom structure mining method based on the collaborative ore collection of blast force and gravity of fan-shaped holes, including the following steps: S1. Determine the stope layout form according to the occurrence form of the deep thick and large ore body, the in-situ stress condition, the stope size and the location of the development project, divide the stope and determine the target stope; S2. Construct an upper stope connecting roadway and a drilling roadway from the upper part of the target stope. The upper stope connecting roadway communicates with the drilling roadway. Construct a lower stope connecting roadway and an ore-drawing roadway from the lower part of the target stope. The lower stope connecting roadway communicates with the ore-drawing roadway. Construct a bottom-drawing crossheading connecting with the ore-drawing roadway from the target stope, and use the bottom-drawing crossheading as the initial free face and compensation space to construct the target stope to form a first cut slot, and the first cut slot communicates the drilling roadway with the bottom-drawing crossheading. S3. Determine the blasting excavation face in the target stope, and construct first downward fan-shaped blast holes downward in the drilling roadway until the blasting excavation face. The depth of the first downward fan-shaped blast holes decreases from the first cut slot to the end of the target stope. Construct upward fan-shaped blast holes from the ore-drawing roadway until the blasting excavation face. The depth of the upward fan-shaped blast holes increases from the first cut slot to the end of the target stope. S4. Load explosives into the first downward fan-shaped blast holes and the upward fan-shaped blast holes, blast the first downward fan-shaped blast holes and the upward fan-shaped blast holes in sequence, and ore the caved ore through the ore-drawing roadway in sequence. S5. Fill the goaf formed in the target stope.

[0006] Optionally, constructing an upper stope connecting roadway and a drilling roadway from the upper part of the target stope, and the upper stope connecting roadway communicates with the drilling roadway, includes: Upper stage roadways are opened on both sides of the upper part of the target stope. The upper stope connecting roadway is constructed from the upper stage roadway to the target stope, and the drilling roadway is arranged along the stope extraction direction at the upper part of the target stope.

[0007] Optionally, constructing a lower stope connecting roadway and an ore-drawing roadway from the lower part of the target stope, and the lower stope connecting roadway communicates with the ore-drawing roadway, includes: Lower stage roadways are opened on both sides of the lower part of the target stope. The lower stope connecting roadway is constructed from the lower stage roadway to the target stope, and the ore-drawing roadway is arranged along the stope extraction direction at the lower part of the target stope.

[0008] Optionally, constructing a bottom-drawing crossheading connecting with the ore-drawing roadway from the target stope, and using the bottom-drawing crossheading as the initial free face and compensation space to construct the target stope to form a first cut slot, and the first cut slot communicates the drilling roadway with the bottom-drawing crossheading, includes: Construct the bottom-drawing crossheading along the direction perpendicular to the ore-drawing roadway at the lower part of the target stope, drill second downward fan-shaped blast holes in the rock-drilling roadway, load explosives into the second downward fan-shaped blast holes, and conduct layered blasting with the bottom-drawing crossheading as the initial free face and compensation space to form the first cutting slot.

[0009] Optionally, the width of the bottom-drawing crossheading is 3m - 5m, and the length is the width of the target stope.

[0010] Optionally, the inclination angle of the blasting excavation surface is equal to the natural angle of repose of the caved ore bulk.

[0011] Optionally, the distance between the bottom of the first downward fan-shaped blast hole and the top of the ore-drawing roadway is not less than 5m.

[0012] Optionally, load explosives into the first downward fan-shaped blast hole and the upward fan-shaped blast hole, blast the first downward fan-shaped blast hole and the upward fan-shaped blast hole in sequence, and successively extract the caved ore through the ore-drawing roadway, including: After loading explosives into the first downward fan-shaped blast hole, detonate the first downward fan-shaped blast hole in sectional sequence to side-collapse the ore body in the target stope above the blasting excavation surface. The caved ore falls through the first cutting slot and is transported out through the ore-drawing roadway until the ore extraction is completed; After the ore extraction of the ore body in the target stope above the blasting excavation surface is completed, load explosives into the upward fan-shaped blast hole, detonate the upward fan-shaped blast hole in sectional sequence to side-collapse the ore body in the target stope below the blasting excavation surface. The caved ore is transported out through the ore-drawing roadway until the ore extraction is completed.

[0013] Optionally, fill the goaf formed in the target stope, including: Lower the filling pipeline to the goaf through the rock-drilling roadway, and fill the filling material into the goaf through the filling pipeline.

[0014] Optionally, use a long cable bolt and bolt support system to provide pre-support for the upper stope connecting roadway, the rock-drilling roadway, the lower stope connecting roadway, and the ore-drawing roadway.

[0015] Beneficial effects In the embodiments of the present invention, the flat-bottom structure mining method based on the combined blasting force and gravity of fan-shaped holes has the advantages of simple stope structure, small mining engineering quantity, high mining efficiency, high ore recovery rate, easy control of ground pressure, and favorable for the bearing of backfill. By decreasing the depth of the first downward fan-shaped blast holes from the first cut groove towards the end of the target stope, a blasting excavation surface that inclines towards the first cut groove area and adapts to the natural angle of repose of the caved ore and rock is formed. This enables the caved ore to gather towards the ore-drawing roadway under the action of gravity and blasting force, improving the ore-drawing efficiency of the stope and controlling the ore-drawing quantity of the remote-controlled load-haul-dump machine. In addition, the blasting excavation surface that inclines towards the first cut groove area keeps the caved ore in a flowing state under the action of ore-drawing disturbance and gravity, avoiding the caking of ore. Using the first downward fan-shaped blast holes instead of vertical medium-deep holes for blasting ore caving changes the top of the target stope from a rectangular shape to an arch structure, reducing the stress concentration on the roof of the target stope, facilitating ground pressure prevention and control while reducing the development and preparation engineering quantity; the arch structure at the top is favorable for the bearing of backfill, reducing the requirements for backfill contact with the roof; workers construct in the well-supported stope drilling roadway and ore-drawing roadway, with good safety. Compared with the traditional "V"-shaped trench ore-drawing structure, it has the advantage of simple mining engineering design, avoiding the problem of driving roadways in the backfill in the second-step stope stoping, and improving the production efficiency of the mine; using the mining method of the present invention avoids the setting of peach-shaped ore pillars, reducing ore loss and having good economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flow chart of the present invention; Figure 2 is a schematic cross-sectional structure diagram of the target stope of the present invention; Figure 3 is of the present invention Figure 2 D-D cross-sectional structure diagram; Figure 4 is a blasting sequence structure diagram of the first cut groove of the present invention; Figure 5 is of the present invention Figure 2 A-A cross-sectional structure diagram; Figure 6 is of the present invention Figure 2 B-B cross-sectional structure diagram; Figure 7 is of the present invention Figure 2 C-C cross-sectional structure diagram; Figure 8 is a schematic diagram of the ore caving sequence of the target stope of the present invention.

[0017] The reference numerals are shown as: 1. Target stope; 2. Upper stope connecting roadway; 3. Drifting roadway; 4. Lower stope connecting roadway; 5. Ore-drawing roadway; 6. Undercutting crossheading; 7. First cut; 8. Blasting excavation face; 9. First downward fan-shaped blast hole; 10. Upward fan-shaped blast hole; 11. Upper stage roadway; 12. Lower stage roadway; 13. Second downward fan-shaped blast hole. Detailed implementation manners

[0018] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0019] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0020] In the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] The following describes the preferred embodiments of the present invention with reference to the drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention and are not used to limit the present invention.

[0022] Combined with Figures 1-8 As shown, according to the embodiment of the present application, a flat-bottom structure mining method based on the cooperation of fan-shaped hole blasting force and gravity for ore collection is provided, including the following steps: S1. Determine the stope layout form according to the occurrence form of deep massive ore bodies, in-situ stress conditions, stope dimensions and the location of development engineering, divide the stope and determine the target stope 1.

[0023] Specifically, in the mining of deep and thick ore bodies, it is necessary to scientifically determine the stope layout form, reasonably divide the stopes and select the target stope 1. This process needs to comprehensively consider core factors such as the occurrence form of the ore body, in-situ stress conditions, stope dimensions, and the location of development engineering. An efficient and safe mining system is constructed through systematic analysis.

[0024] S2. Construct the upper stope connecting drift 2 and the drilling drift 3 from the upper part of the target stope 1. The upper stope connecting drift 2 is connected to the drilling drift 3. Construct the lower stope connecting drift 4 and the ore-drawing drift 5 from the lower part of the target stope 1. The lower stope connecting drift 4 is connected to the ore-drawing drift 5. Construct the undercut cross drift 6 connecting to the ore-drawing drift 5 from the target stope 1, and use the undercut cross drift 6 as the initial free face and compensation space to construct the target stope 1 to form the first cut slot 7. The first cut slot 7 connects the drilling drift 3 and the undercut cross drift 6.

[0025] Specifically, the construction of the upper stope connecting drift 2 is the prerequisite for ensuring the smooth progress of the drilling operation in the target stope 1. Through the opening of the upper stope connecting drift 2, the drilling drift 3 is opened in the upper part of the target stope 1, and the target stope 1 is connected to the upper stage drift 11 to form a closed ventilation, construction, and transportation loop. Open the lower stope connecting drift 4 and the ore-drawing drift 5 in the lower part of the target stope 1, which can provide smooth passage for ore-drawing equipment such as load-haul-dump machines and remote-controlled load-haul-dump machines for ore transportation and ore drawing. Construct the undercut cross drift 6 connecting to the ore-drawing drift 5 in the lower part of the target stope 1. Using the undercut cross drift 6 as the initial free face and compensation space, the first cut slot 7 connecting the drilling drift 3 and the undercut cross drift 6 is formed by the VCR stratified directional blasting technology. The opening of the first cut slot 7 can provide the initial free face and compensation space for subsequent blasting, improve the blasting effect, and at the same time provide a collecting space for subsequent blasting ore caving, so that the caved ore is concentrated in the first cut slot 7, which is convenient for ore drawing from the ore-drawing drift 5 and improves the ore-drawing efficiency of the stope.

[0026] S3. Determine the blasting excavation surface 8 in the target stope 1. Drill the first downward fan-shaped blast holes 9 downward from the drilling drift 3 until the blasting excavation surface 8. The depth of the first downward fan-shaped blast holes 9 decreases from the first cut slot 7 to the end of the target stope 1. Drill the upward fan-shaped blast holes 10 from the ore-drawing drift 5 until the blasting excavation surface 8. The depth of the upward fan-shaped blast holes 10 increases from the first cut slot 7 to the end of the target stope 1.

[0027] Specifically, the first downward fan-shaped blast hole 9 is constructed downward from the drifting roadway 3, and its depth decreases from the first cut groove 7 towards the ends on both sides of the target stope 1, so as to ensure that after blasting, the ore forms a blasting excavation surface 8 that slopes upward from the first cut groove 7 towards the ends on both sides of the target stope 1. Near the first cut groove 7, the depth of the blast hole is relatively deep. As it extends towards the end of the target stope 1, the depth of the blast hole gradually becomes shallower. This arrangement with decreasing depth makes the excavation surface after blasting slope towards the first cut groove 7, facilitating the natural sliding and accumulation of the ore towards the first cut groove 7 area under the action of gravity and blasting force, reducing the accumulation of ore in the target stope 1, improving the ore drawing efficiency, and enabling the load-haul-dump machine to directly load the blasted ore in the ore-drawing roadway 5.

[0028] The upward fan-shaped blast hole 10 is constructed upward from the ore-drawing roadway 5, and its depth increases from the first cut groove 7 towards the end of the target stope 1, forming a complement with the first downward fan-shaped blast hole 9 to ensure that all the ore in the target stope 1 can be effectively blasted and broken, avoiding the generation of large blasted pieces and ensuring the blasting effect of the stope. As the blasting progresses towards the target stope 1, the ore after blasting from the upward fan-shaped blast hole 10 accumulates towards the ore-drawing roadway 5 under the action of blasting force and gravity, realizing the all-round crushing and efficient handling of the ore in the target stope 1, reducing the ore residue, and improving the ore recovery rate.

[0029] By using the first downward fan-shaped blast hole 9 to replace the traditional vertical medium-deep hole for blasting and ore caving, and the drifting roadway 3 to replace the traditional top-drilling chamber, the exposed area of the roof is reduced, facilitating the control of the ground pressure in the stope. Workers carry out drilling operations in the drifting roadway 3 with good safety. The goaf changes from a rectangular structure formed by traditional blasting to an arch structure, slowing down the stress concentration, facilitating the control of ground pressure while reducing the excavation and mining workload. The arch structure is beneficial for the bearing of the filling body after excavation and mining, reducing the requirement for filling to reach the roof.

[0030] S4. Load explosives into the first downward fan-shaped blast hole 9 and the upward fan-shaped blast hole 10, blast the first downward fan-shaped blast hole 9 and the upward fan-shaped blast hole 10 in sequence, and draw the caved ore through the ore-drawing roadway 5 in sequence.

[0031] Specifically, based on the depths, angles, and rock properties of the first downward fan-shaped blast holes 9 and upward fan-shaped blast holes 10, calculate the explosive charge amount and charging method. For the first downward fan-shaped blast holes 9, due to the relatively dense arrangement of the blast holes, interval charging is advisable to reduce the fine ore rate. To reduce large block blasting, millisecond bottom initiation is advisable. Considering that the upward fan-shaped blast holes 10 are close to the ore-drawing roadway 5, to avoid damaging the roadway structure during blasting, uncoupled charging and interval stemming are adopted for the blast holes, leaving an air gap between the blast hole wall and the explosive to reduce the impact of the explosion stress wave on the roadway. During the charging process, strictly implement the safety operation procedures and use special charging equipment to ensure that the explosive is evenly distributed in the blast holes, preventing blockage, discontinuous charging, etc., creating good conditions for subsequent blasting. After blasting, the ore enters the ore-drawing roadway 5 through the first cutting groove 7 for ore drawing. S5. Fill the goaf formed in the target stope 1.

[0032] Specifically, after ore drawing is completed, according to the mine production technical conditions, tailings filling, tailings cemented filling, waste rock filling, waste rock cemented filling, etc. can be selected to fill the goaf.

[0033] Combined with Figure 1 、 Figure 2 、 Figure 5 As shown, in the embodiment of the present application, the upper stope connecting roadway 2 and the drilling roadway 3 are constructed from the upper part of the target stope 1. The upper stope connecting roadway 2 is connected to the drilling roadway 3, including: Upper stage roadways 11 are opened on both sides of the upper part of the target stope 1. The upper stope connecting roadway 2 is constructed from the upper stage roadway 11 to the target stope 1, and the drilling roadway 3 is arranged along the extraction direction of the target stope 1 at the upper part of the target stope 1.

[0034] Specifically, the upper stope connecting roadway 2 is constructed from the upper stage roadways 11 on both sides of the upper part of the target stope 1 towards the target stope 1, connecting the target stope 1 and the mine development system, forming a closed ventilation and transportation loop, providing an engineering foundation for workers to enter the drilling roadway 3 for construction. After the upper stope connecting roadway 2 is formed, the drilling roadway 3 is constructed along the extraction direction of the upper part of the target stope 1. The space after its construction directly affects the construction quality and blasting effect of the first downward fan-shaped blast holes 9. Before layout, according to the parameters of the first downward fan-shaped blast holes 9 in the mining design of the target stope 1, calculate the space of the drilling roadway 3. At the same time, sufficient space is reserved in the drilling roadway 3 for arranging drilling equipment, water and air pipelines, and cable lines, creating an operating environment for the subsequent construction of the first downward fan-shaped blast holes 9. Combined with Figure 1 、 Figure 2 、 Figure 3 、 Figure 5As shown in the figure, in the embodiment of the present application, the lower stope connecting roadway 4 and the ore-drawing roadway 5 are constructed from the lower part of the target stope 1. The lower stope connecting roadway 4 is connected to the ore-drawing roadway 5, including: Lower stage roadways 12 are opened on both sides of the lower part of the target stope 1. The lower stope connecting roadway 4 is constructed from the lower stage roadway 12 towards the target stope 1, and the ore-drawing roadway 5 is arranged along the mining direction of the target stope 1 at the lower part of the target stope 1.

[0035] Specifically, the lower stope connecting roadway 4 is constructed from the lower stage roadways 12 on both sides of the lower part of the target stope 1 towards the target stope 1. This construction method relying on the existing development engineering greatly reduces the drivage work volume and construction cost. The ore-drawing roadway 5 is constructed along the mining direction at the lower part of the target stope 1. Before construction, factors such as ore body thickness, mining method, and performance of ore-drawing equipment are comprehensively considered to calculate the dimensions of the ore-drawing roadway 5, ensuring that the dimensions of the ore-drawing roadway can meet the requirements of the mine production capacity. The layout of facilities such as cables, air and water pipelines, and drainage pipelines is reasonably planned in the ore-drawing roadway 5, leaving enough space for the operation and maintenance of ore-drawing equipment, and installing lighting, communication, and monitoring equipment to create a safe and convenient environment for ore-drawing operations. The blasted ore is collected in the ore-drawing roadway 5 and then transported to the main haulage roadway through the lower stope connecting roadway 4 and the lower stage roadway 12, and finally transported to the concentrator. Ore-drawing equipment such as remote-controlled load-haul-dump machines can enter the ore-drawing roadway 5 through the lower stope connecting roadway 4, improving the ore-drawing efficiency. Combined with Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 As shown in the figure, in the embodiment of the present application, the undercut crossheading 6 connected to the ore-drawing roadway 5 is constructed from the target stope 1, and the first cut slot 7 is formed by constructing the target stope 1 with the undercut crossheading 6 as the initial free surface and compensation space. The first cut slot 7 connects the drifter roadway 3 and the undercut crossheading 6, including: The undercut crossheading 6 is constructed along the direction perpendicular to the ore-drawing roadway 5 at the lower part of the target stope 1. The second downward fan-shaped blast holes 13 are opened in the drifter roadway 3, explosives are loaded into the second downward fan-shaped blast holes 13, and the first cut slot 7 is formed by layered blasting with the undercut crossheading 6 as the initial free surface and compensation space.

[0036] Specifically, the bottom-drawing crossheading 6 is constructed at the lower part of the target stope 1 in a direction perpendicular to the ore-drawing roadway 5. While ensuring that the subsequent first cutting slot 7 can be smoothly connected to the ore-drawing roadway 5, it provides sufficient free face and compensation space for the layered blasting excavation of the first cutting slot 7. In the drilling roadway 3, the second downward fan-shaped blast holes 13 are opened according to the position of the bottom-drawing crossheading 6 and the designed shape of the first cutting slot 7. Explosives are loaded into the second downward fan-shaped blast holes 13, and the VCR layered blasting method is used to conduct blasting in sequence from bottom to top. After the rock is broken, it collapses towards the bottom-drawing crossheading 6, gradually forming the first cutting slot 7 with a predetermined shape and size. This layered blasting method not only effectively controls the impact of blasting vibration on the surrounding rock of the stope, but also ensures the forming accuracy of the first cutting slot 7, avoids over-excavation or under-excavation phenomena, and avoids the construction of the cutting raise. It has the advantages of high construction efficiency and good safety.

[0037] Set Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 As shown, in the embodiment of the present application, the width of the bottom-drawing crossheading 6 is 3m - 5m, and the length is the width of the target stope 1.

[0038] Specifically, through the setting of the width of the bottom-drawing crossheading 6 being 3m - 5m, a wider roadway can meet the flexible operation and parallel operation of large construction equipment such as a jumbo and a loading machine. Especially in deep and complex geological conditions, it is convenient for the equipment to quickly adjust its position and respond to emergencies, improving construction efficiency; the setting of the length being the same as the width of the target stope 1 ensures that the bottom-drawing crossheading 6 can completely cover the bottom transverse area of the target stope 1, providing sufficient free face and compensation space for the subsequent first cutting slot 7, and ensuring that the ore can be evenly broken and smoothly converge towards the ore-drawing roadway 5 during blasting ore caving. Combined with Figure 1 、 Figure 2 As shown, in the embodiment of the present application, the inclination angle of the blasting excavation surface 8 is equal to the natural angle of repose of the caved ore bulk.

[0039] Specifically, when the inclination angle of the blasting excavation surface 8 is equal to the natural angle of repose of the caved ore loose body, the caved ore is in a critically stable state under the action of gravity. The natural angle of repose is the maximum stable angle that the slope of the ore loose body can form with the horizontal plane when it accumulates without external interference. At this time, under the action of gravity, the blasted ore only needs a very small external force (such as the residual blasting force generated by blasting and the mutual collision force between ores) to start sliding downward along the blasting excavation surface 8, enabling the ore to converge towards the ore-drawing roadway 5, reducing the residence time and accumulation amount of the ore in the stope, and greatly improving the ore-drawing efficiency. At the same time, this stable ore flow state avoids the impact force generated by the sudden sliding or collapse of the ore, reduces the pressure fluctuation on the roof and side walls of the target stope 1, helps to maintain the stability of the stope surrounding rock, and creates a safe environment for subsequent operations.

[0040] Combined with Figure 5 , Figure 6 , Figure 7 As shown, in the embodiment of the present application, the distance between the bottom of the first downward fan-shaped blast hole 9 and the top of the ore-drawing roadway 5 is not less than 5 m.

[0041] Specifically, by setting the distance between the bottom of the first downward fan-shaped blast hole 9 and the top of the ore-drawing roadway 5 to be not less than 5 m, this distance setting effectively reduces the risk of impact damage to the ore-drawing roadway 5 during blasting operations. During blasting, the stress wave and impact energy generated by the explosion of explosives will spread to the surrounding area. If the bottom of the first downward fan-shaped blast hole 9 is too close to the top of the ore-drawing roadway 5, the strong impact energy may cause the rock mass at the top of the roadway to break and crack, or even lead to the collapse of the roadway. When the distance is not less than 5 m, there is enough rock mass medium for buffering and attenuation during the propagation of the stress wave, greatly reducing the energy intensity transmitted to the top of the ore-drawing roadway 5. At the same time, this distance also reserves enough safety thickness for the ore-drawing roadway 5. Even if some rock masses have cracks due to blasting, they can rely on their own structural strength and support measures to maintain stability, ensuring the safe operation of equipment and personnel in the ore-drawing roadway 5. In addition, during the subsequent ore-drawing process, if the caving shape of the ore near the bottom of the hole is abnormal due to blasting, the large distance can also prevent the ore from directly impacting the top of the ore-drawing roadway 5, preventing the ore from damaging the equipment and facilities in the roadway and reducing the possibility of safety accidents. Combined with Figure 1 , Figure 2 , Figure 5 , Figure 6 , Figure 7 As shown, in the embodiment of the present application, explosives are loaded into the first downward fan-shaped blast hole 9 and the upward fan-shaped blast hole 10, and the first downward fan-shaped blast hole 9 and the upward fan-shaped blast hole 10 are blasted in sequence, and the caved ore is drawn through the ore-drawing roadway 5 in sequence, including: After filling the first downward fan-shaped blast hole 9 with explosive, the first downward fan-shaped blast hole 9 is detonated in a segmented sequence to side-collapse the ore body of the target stope 1 above the blasting excavation face 8. The caved ore falls through the first cutting groove 7 and is transported out through the ore-drawing roadway 5 until the ore-drawing is completed.

[0042] After the ore-drawing of the ore body of the target stope 1 above the blasting excavation face 8 is completed, the upward fan-shaped blast hole 10 is filled with explosive, and the upward fan-shaped blast hole 10 is detonated in a segmented sequence to side-collapse the ore body of the target stope 1 below the blasting excavation face 8. The caved ore is transported out through the ore-drawing roadway 5 until the ore-drawing is completed.

[0043] Specifically, the explosive filling, sequential blasting, and ore-drawing operations of the first downward fan-shaped blast hole 9 and the upward fan-shaped blast hole 10 are important processes for realizing efficient ore extraction and safe transportation. The sequence is as follows: First, fill the first downward fan-shaped blast hole 9 on one side of the first cutting groove 7 with explosive, and then, in the order from the first cutting groove 7 to the end of the target stope 1, detonate the first downward fan-shaped blast hole 9 row by row, so that the ore slides towards the first cutting groove 7 under the action of blasting force and gravity, enters the ore-drawing roadway 5, and the ore is drawn through the ore-drawing roadway 5 by a load-haul-dump machine. After the ore-drawing is completed; fill the first downward fan-shaped blast hole 9 on the other side of the first cutting groove 7 with explosive, and then, in the order from the first cutting groove 7 to the end of the target stope 1, detonate the first downward fan-shaped blast hole 9 row by row, so that the ore slides towards the first cutting groove 7 under the action of blasting force and gravity, enters the ore-drawing roadway 5, and the ore is drawn through the ore-drawing roadway 5 by a load-haul-dump machine. After the ore-drawing is completed; fill the upward fan-shaped blast hole 10 on one side of the first cutting groove 7 with explosive, and then, in the order from the first cutting groove 7 to the end of the target stope 1, detonate the upward fan-shaped blast hole 10 row by row, so that the ore enters the ore-drawing roadway 5 under the action of blasting force and gravity, and the ore is drawn through the ore-drawing roadway 5 by a remote-controlled load-haul-dump machine. After the ore-drawing is completed; fill the upward fan-shaped blast hole 10 on the other side of the first cutting groove 7 with explosive, and then, in the order from the first cutting groove 7 to the end of the stope, detonate the upward fan-shaped blast hole 10 row by row, so that the ore enters the ore-drawing roadway 5 under the action of blasting force and gravity, and the ore is drawn through the ore-drawing roadway 5 by a remote-controlled load-haul-dump machine. In the embodiment of the present application, filling the goaf formed in the target stope 1 includes: The filling pipeline is lowered into the goaf through the drifter roadway 3, and the filling material is filled into the goaf through the filling pipeline.

[0044] Combined with Figure 1 、 Figure 2 As shown, in the embodiment of the present application, the upper stope connecting roadway 2, the drifter roadway 3, the lower stope connecting roadway 4, and the ore-drawing roadway 5 are provided with pre-support by a long cable bolt and rock bolt support system.

[0045] Specifically, after the construction of the upper stope connecting roadway 2, the drilling roadway 3, the lower stope connecting roadway 4, and the ore-drawing roadway 5 is completed, a long cable bolt and bolt support system is used for pre-support to ensure the stability of the roadway and the safety of mining operations. A steel mesh can be laid on the surface of the roadway and concrete can be sprayed to form a combined support system of "long cable bolt + bolt + steel mesh + sprayed concrete", enhancing the impact resistance of the roadway surface and preventing rock blocks from falling.

[0046] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included within the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art in the technical field of the present application, several improvements and modifications can be made without departing from the technical principle of the present application, and these improvements and modifications should also be regarded as within the protection scope of the present application.

Claims

1. A flat-bottom structure mining method based on the combined blasting-gravity ore collection of fan-shaped holes, characterized in that, It includes the following steps: S1. Determine the stope layout form according to the occurrence form of deep and massive ore bodies, in-situ stress conditions, stope dimensions and the location of development engineering, divide the stope and determine the target stope (1); S2. Construct the upper stope connecting roadway (2) and the drilling roadway (3) from the upper part of the target stope (1), and the upper stope connecting roadway (2) is connected to the drilling roadway (3); construct the lower stope connecting roadway (4) and the ore-drawing roadway (5) from the lower part of the target stope (1), and the lower stope connecting roadway (4) is connected to the ore-drawing roadway (5); construct the undercut crossheading (6) connected to the ore-drawing roadway (5) from the target stope (1), and use the undercut crossheading (6) as the initial free face and compensation space to construct the target stope (1) to form the first cut slot (7), and the first cut slot (7) connects the drilling roadway (3) and the undercut crossheading (6); S3. Determine the blasting excavation surface (8) in the target stope (1), construct the first downward fan-shaped blast holes (9) downward in the drilling roadway (3) until the blasting excavation surface (8), and the depth of the first downward fan-shaped blast holes (9) decreases from the first cut slot (7) to the end of the target stope (1); construct the upward fan-shaped blast holes (10) from the ore-drawing roadway (5) until the blasting excavation surface (8), and the depth of the upward fan-shaped blast holes (10) increases from the first cut slot (7) to the end of the target stope (1); S4. Load explosives into the first downward fan-shaped blast holes (9) and the upward fan-shaped blast holes (10), blast the first downward fan-shaped blast holes (9) and the upward fan-shaped blast holes (10) in sequence, and draw out the blasted ore through the ore-drawing roadway (5) in turn; S5. Fill the goaf formed in the target stope (1).

2. The flat-bottom structure mining method based on the collaborative ore collection of blasting force and gravity with fan-shaped holes according to claim 1, wherein Construct the upper stope connecting roadway (2) and the drilling roadway (3) from the upper part of the target stope (1), and the upper stope connecting roadway (2) is connected to the drilling roadway (3), including: Upper stage roadways (11) are opened on both sides of the upper part of the target stope (1), the upper stope connecting roadway (2) is constructed from the upper stage roadway (11) to the target stope (1), and the drilling roadway (3) is arranged along the stoping direction of the target stope (1) at the upper part of the target stope (1).

3. The flat-bottom structure mining method based on the combined blasting-gravity ore collection of fan-shaped holes according to claim 2, wherein, Construct the lower stope connecting roadway (4) and the ore-drawing roadway (5) from the lower part of the target stope (1), and the lower stope connecting roadway (4) is connected to the ore-drawing roadway (5), including: Lower stage roadways (12) are opened on both sides of the lower part of the target stope (1), the lower stope connecting roadway (4) is constructed from the lower stage roadway (12) to the target stope (1), and the ore-drawing roadway (5) is arranged along the stoping direction of the target stope (1) at the lower part of the target stope (1).

4. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 3, characterized in that, Construct a sill crossheading (6) connecting the target stope (1) to the ore-drawing roadway (5), and use the sill crossheading (6) as the initial free face and compensation space to construct the first cut groove (7) in the target stope (1). The first cut groove (7) connects the drilling roadway (3) and the sill crossheading (6), including: Construct the sill crossheading (6) in the lower part of the target stope (1) along the direction perpendicular to the ore-drawing roadway (5). Drill second downward fan-shaped blast holes (13) in the drilling roadway (3), load explosives into the second downward fan-shaped blast holes (13), and conduct stratified blasting with the sill crossheading (6) as the initial free face and compensation space to form the first cut groove (7).

5. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 4, characterized in that The width of the sill crossheading (6) is 3 m - 5 m, and the length is the width of the target stope (1).

6. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 1, characterized in that The inclination angle of the blasting excavation surface (8) is equal to the natural angle of repose of the caved ore bulk.

7. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 1, characterized in that The distance between the bottom of the first downward fan-shaped blast hole (9) and the top of the ore-drawing roadway (5) is not less than 5 m.

8. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 1, characterized in that, Load explosives into the first downward fan-shaped blast holes (9) and the upward fan-shaped blast holes (10), blast the first downward fan-shaped blast holes (9) and the upward fan-shaped blast holes (10) in sequence, and successively draw out the caved ore through the ore-drawing roadway (5), including: After loading explosives into the first downward fan-shaped blast holes (9), detonate the first downward fan-shaped blast holes (9) in segmented sequence to side-collapse the ore body in the target stope (1) above the blasting excavation surface (8). The caved ore falls through the first cut groove (7) and is transported out through the ore-drawing roadway (5) until the ore drawing is completed; After the ore drawing of the ore body in the target stope (1) above the blasting excavation surface (8) is completed, load explosives into the upward fan-shaped blast holes (10), detonate the upward fan-shaped blast holes (10) in segmented sequence to side-collapse the ore body in the target stope (1) below the blasting excavation surface (8). The caved ore is transported out through the ore-drawing roadway (5) until the ore drawing is completed.

9. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 1, characterized in that, Fill the goaf formed in the target stope (1), including: Lower the filling pipeline through the drilling roadway (3) into the goaf, and fill the filling material into the goaf through the filling pipeline.

10. The flat-bottom structure mining method based on the combined blasting-gravity ore collection with fan-shaped holes according to claim 1, characterized in that Provide pre-support for the upper stope connecting roadway (2), the drilling roadway (3), the lower stope connecting roadway (4), and the ore-drawing roadway (5) using a long cable bolt and rock bolt support system.

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