Downward-entry filling and subsequent filling in the medium-deep hole stage, based on the upper support, are combined mining methods.

Abstract

This invention provides a combined mining method based on hanging wall support, involving downward approach filling and subsequent filling in medium-deep holes. The ore body is inclined and the hanging wall is fractured. The method includes the following steps: dividing the ore body into stops and pillars, and dividing the ore block into N layers from top to bottom; using a specific external inclined ramp as a preparatory engineering project; first, using the downward approach filling method to recover the stope; then using the medium-deep hole subsequent filling method with simultaneous blasting from both top and bottom to recover the pillars. This invention can provide diversified and effective support for the hanging wall of the ore body. The downward approach mining of the stope ensures the stability of the approach roof and the filling bodies on both sides. The medium-deep hole caving method is used for the pillars, and pre-installed polyurethane foam material serves as a cutting shaft, greatly improving mining efficiency. The inclined ramp serves as both a development and preparatory engineering project, effectively reducing the amount of tunneling work, shortening the mining preparation time, and improving mining efficiency, making it highly valuable for widespread application.

Description

Technical Field

[0001] This invention relates to the field of ore body mining technology, and in particular to a mining method based on hanging wall support, including downward access filling and subsequent filling in the medium-deep hole stage. Background Technology

[0002] For mining thick, dipping ore bodies with fractured hanging wall, the upward approach mining method is typically used. These ore bodies usually have a dip angle of 40–55° and a thickness of 50–60 m. The fractured hanging wall is a major factor limiting efficient mining of these ore bodies. The upward approach mining method typically involves dividing the ore body into blocks along the strike, with each block approximately 10 m wide and the length equal to the extension of the ore body. Preparatory work mainly consists of sectional haulage roadways and stope-to-stope connecting roadways. Mining begins in the stope-to-stope connecting roadway, proceeding from the footwall to the hanging wall. Roof support is provided as mining progresses. After reaching the hanging wall, the surrounding rock is supported. Backfilling is performed after the lowest level is mined, and then the next layer is mined. This mining method results in a relatively small exposed area of ​​the stope roof and hanging wall, allowing for timely support of the surrounding rock after construction, which helps ensure safety during stope construction. However, with the depletion of shallow mineral resources in my country, mines have gradually shifted to deep mining. The high-stress environment has led to safety hazards in the mine roof and a sharp increase in mining costs. There is an urgent need to find a safer and more efficient mining method to recover deep resources.

[0003] Patent CN112502709B discloses a pre-controlled intelligent mining method for vertical medium-deep hole VCR caving and immediate post-blast backfilling. The method divides the ore body into three zones: the hanging wall VCR caving zone, the footwall VCR caving zone, and the footwall lateral caving zone. The VCR method is used for separate mining and backfilling in these three zones. Specifically, the hanging wall VCR caving zone is mined using a single blast caving followed by cemented backfilling; the footwall VCR caving zone is mined using alternating rows of VCR blasting and cemented backfilling; and the footwall lateral caving zone is mined using alternating rows of blasting followed by a single cemented backfilling. This method can improve production efficiency and ensure the safety of the stope roof to a certain extent. However, the following drawbacks still exist: (1) When mining the VCR collapse zone of the upper hanging wall, the surrounding rock of the upper hanging wall was not supported. During mining, the ore dilution rate is easily increased due to the falling of the surrounding rock of the upper hanging wall. In addition, the large-scale collapse of the surrounding rock of the upper hanging wall can easily cover the ore, resulting in an increased loss rate; (2) Due to the large height of the stope and the disturbance caused by mining blasting, the filling body of the adjacent stope that has been mined has peeled off in a large area, resulting in an increased ore dilution rate; (3) The remote-controlled loader technology is not yet mature, and the ore extraction efficiency needs to be verified.

[0004] Patent CN110219650B discloses a deep-hole subsequent backfilling mining method for environmental remediation stages. The method divides the ore body into panels and blocks, with each block further divided into first-stage and second-stage stopes for mining in two steps. First, a run-through backfilling method is used to mine the ore body within the upper pillar area of ​​both the first-stage and second-stage stopes, as well as the ore body at the bottom of the second-stage stope, using high-strength cemented backfill. Then, a run-through backfilling method is used to mine the ore body in the hanging wall of both the first-stage and second-stage stopes. Finally, a staged deep-hole subsequent backfilling method is used to mine the second-stage stope. The shortcomings of this method are: (1) The preparation work includes segmented transport roadways, ore chutes, ore collection trenches and external inclined ramps, etc., and the preparation work is relatively large; (2) No protective measures are taken for the two sides during the first-step road filling, which will cause disturbance to the filling body during the second-step mining, causing it to fall off, posing a safety hazard and increasing the ore dilution rate; (3) The second-step mining adopts the traditional deep-hole subsequent filling mining method, which has low mining efficiency.

[0005] In view of this, it is necessary to design an improved mining method based on the upper support, downward approach filling and subsequent filling in the medium-deep hole stage, to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage, based on the upper support of the ore body. This method can provide diversified and effective support for the upper part of the ore body. Simultaneously, the use of downward approach mining in the stope ensures the stability of the approach roof and the filling bodies on both sides. The pillars are constructed using the medium-deep hole caving method, and pre-installed polyurethane foam material serves as a cutting shaft, greatly improving mining efficiency. The inclined ramp also serves as a development and preparation engineering facility, effectively reducing the amount of tunneling work, shortening mining preparation time, and improving mining efficiency, thus possessing extremely high value for widespread application.

[0007] To achieve the above-mentioned objectives, this invention provides a combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on the upper support, wherein the ore body is inclined and the upper hanging wall is fractured; the method includes the following steps:

[0008] S1. Divide the ore body into several blocks along the strike of the ore body, and mine the blocks as units; within each block, divide it into stops and pillars at intervals perpendicular to the strike of the ore body, and divide the block into N layers from top to bottom;

[0009] S2. Construct an external inclined ramp with a preset slope along the strike of the ore body on the footwall side; the vertical height of the external inclined ramp is equal to the height of the ore block, and ensure that each horizontal connecting road constructed perpendicular to the strike of the ore body from the external inclined ramp corresponds to a random stope.

[0010] S3. From the inclined ramp outside the vein, construct the first layer of horizontal layer-changing connecting road perpendicular to the ore body to the footwall; continue excavating the stope corresponding to the first layer of horizontal layer-changing connecting road to the hanging wall; at the hanging wall, excavate along the vein of the hanging wall until both sides of the ore body, supporting as mining progresses; from the hanging wall to the footwall, excavate the remaining stopes in the first layer to a predetermined distance from the footwall and then fill them; the first stope excavated is filled to a predetermined distance from the footwall; before filling, fix a polyurethane cutting shaft as a compensation space at the central axis of the pillar on the side of the vein away from the hanging wall;

[0011] S4. Repeat step S3, and use the down-pass filling mining method to mine and fill the ore rooms of layers 2 to (N-1), and mine and fill the ore rooms of each layer to the lower plate.

[0012] S5. Repeat step S3 to mine and fill the Nth layer of the ore cell;

[0013] S6. At the footwall of the first layer, the footwall vein is excavated along the ore body direction until both sides of the ore body are reached, and the width of the footwall vein is equal to the preset distance in step S3; then the pillar is excavated from the footwall vein perpendicular to the ore body direction.

[0014] S7. Repeat step S6 to excavate the pillar of the Nth layer. The middle part of the pillar of the Nth layer is mined, and the two sides are reserved to support the ore body above.

[0015] S8. Simultaneously mine the pillars from the 2nd layer and the (N-1)th layer in opposite directions; after mining is completed, fill all the pillars together.

[0016] As a further improvement of the present invention, in step S2, the lengths of the horizontal connecting channels in each layer are equal; the angle between the external inclined ramp and the horizontal plane is θ.

[0017]

[0018] Where H is the height of each layer;

[0019] L1 is the width of each chamber;

[0020] L2 is the width of each pillar.

[0021] As a further improvement of the present invention, in step S3, the polyurethane cutting well is cylindrical in shape; the inclination angle of the polyurethane cutting well is the same as the dip angle of the ore body.

[0022] As a further improvement of the present invention, in step S3, the support structure along the upper plate includes upper plate anchor cables disposed in the upper plate rock strata, chain link mesh disposed on the sidewall of the upper plate, and suspension bars disposed vertically in the upper plate.

[0023] As a further improvement of the present invention, step S3, the support along the upper plate during mining, includes the following steps:

[0024] S31. As the upper plate is constructed along the vein, upper plate anchor cables perpendicular to the upper plate are constructed in the rock strata of the upper plate;

[0025] S32. Fix the chain link mesh on the side of the upper plate away from the upper plate along the vein;

[0026] S33. Vertical suspension rods are provided along the vein of the upper plate; the suspension rods, the upper plate anchor cable, and the chain link mesh are interconnected.

[0027] As a further improvement of the present invention, step S8 specifically includes:

[0028] S81. The vertical strike of the ore body divides each of the ore pillars into M columns from the hanging wall to the footwall;

[0029] S82. Set blast holes on the upper and lower sides of the first column respectively, and excavate simultaneously in opposite directions; after the excavation is completed, excavate the second column, until the Mth column is reached;

[0030] The pillars, which are spaced apart, are mined simultaneously.

[0031] As a further improvement of the present invention, the blasting is carried out in an upward fan-shaped medium-deep hole configuration at the bottom and in a downward parallel medium-deep hole configuration at the top.

[0032] As a further improvement of the present invention, before the mine is filled, the chain link mesh is fixed on both sides; and several suspension rods are used to connect the chain link mesh on both sides at the center line of the two sides.

[0033] As a further improvement of the present invention, the width of the stope is 4 to 6 m, and the width of the pillar is 9 to 11 m; in step S7, the mining width of the pillar in the Nth layer is 2.5 to 3.5 m.

[0034] As a further improvement of the present invention, the width of the ore block is 110-120m and the height is 25-35m; the ore block is divided into 10 layers from top to bottom, and the height of each layer is 2.5-3.5m.

[0035] The beneficial effects of this invention are:

[0036] (1) The present invention provides a mining method based on the upper support, which combines downward approach filling and subsequent filling in the medium-deep hole stage. The ore block is divided into intermittently arranged rooms and pillars, and the ore block is divided into N layers. The downward approach filling method is used to mine the rooms first, and then the novel medium-deep hole subsequent filling method is used to mine the pillars. Only one specific external slope is required. Then, by constructing the horizontal layer-changing connecting road for each layer, several rooms in each layer can be directly mined. The amount of preparation work is greatly reduced, and rapid mining of the ore block can be achieved.

[0037] (2) This invention improves the traditional medium-deep hole subsequent filling method by adopting a new medium-deep hole subsequent filling method that simultaneously excavates the ore pillar from the top and bottom. The blasting methods used at the top and bottom are different. The lower parallel medium-deep hole is constructed at the top, with the blast hole parallel to the hanging wall of the ore body. The upper fan-shaped medium-deep hole is constructed at the bottom. At the same time, polyurethane foam material is used as a cutting well to provide compensation space. The blasting forms a cutting groove, and the upper and lower blast holes are detonated at the same time to facilitate the mining of ore in the lower mining roadway, which greatly improves the mining efficiency.

[0038] (3) This invention can provide diversified and effective support for the hanging wall of the ore body. At the same time, the use of downward access mining in the stope can ensure the stability of the access roof and the backfill on both sides. The pillars adopt the medium-deep hole caving method, and the pre-installed polyurethane foam material serves as the cutting shaft, which greatly improves mining efficiency. The ramp also serves as a development and preparation engineering, effectively reducing the amount of tunneling work, shortening the mining preparation time, and improving mining efficiency. It has extremely high promotion and application value. Attached Figure Description

[0039] Figure 1 This is a top view of the mining chamber of the present invention.

[0040] Figure 2 for Figure 1 Cross-sectional view of section II.

[0041] Figure 3 This is a top view of the first stope after the mining of the present invention is completed.

[0042] Figure 4 for Figure 3 Cross-sectional view of section II.

[0043] Figure 5 This is a top view of the first pillar of the mining process according to the present invention.

[0044] Figure 6 This is a top view of the Nth ore pillar being mined according to the present invention.

[0045] Figure 7 This is a side view of the ore pillars of the second to (N-1) layers mined according to the present invention.

[0046] Figure 8 This is a schematic diagram of the support structure along the upper plate.

[0047] Figure 9 for Figure 8 Enlarged image.

[0048] Figure 10 This is a schematic diagram of the support structure of the mine.

[0049] Figure Labels

[0050] 1-Stop; 2-Pillar; 3-Footwall; 4-External slope; 5-Horizontal connecting passage; 6-Panel; 7-Panel along vein; 8-Footwall along vein; 9-Drilling tunnel; 10-Mining tunnel; 11-Polyurethane cutting shaft; 12-Infill retaining wall; 13-Panel anchor cable; 14-Chain link mesh; 15-Hanging bar; 16-Lower fan-shaped medium-deep hole; 17-Upper parallel medium-deep hole; 18-Connecting bar. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0053] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0054] Please see Figures 1 to 10 As shown, this invention provides a combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on the upper support, where the ore body is inclined and the upper hanging wall is fractured; it includes the following steps:

[0055] S1. Delineating the ore body:

[0056] The ore body is divided into several blocks along its strike, and mining is carried out on a block-by-block basis. Within each block, perpendicular to the strike of the ore body, it is divided into stops 1 and pillars 2; stops 1 serve as a first-stage stope, such as... Figure 1 As shown in Figures 1-1, 1-2, 1-3...; Pillar 2 serves as a two-step stope, as... Figure 1 As shown in 2-1, 2-2, 2-3..., the ore block is divided into N layers from top to bottom. First, the bottom-pass filling method is used to recover the ore chamber 1, and then the new medium-deep hole subsequent filling method is used to recover the ore pillar 2.

[0057] Specifically, the ore block is 110–120 m wide and 25–35 m high; it is divided into 10 layers from top to bottom, each layer being 2.5–3.5 m high. The stope 1 is 4–6 m wide, and the pillar 2 is 9–11 m wide. In some embodiments, the ore block is 115 m wide and 30 m high, divided into 10 layers from top to bottom, each layer being 3 m high; the stope 1 is 5 m wide, and the pillar 2 is 10 m wide.

[0058] S2. Setting up the preparation work:

[0059] An external inclined ramp 4 with a predetermined slope is constructed along the strike of the ore body on one side of the footwall 3. The vertical height of the external inclined ramp 4 is equal to the height of the ore block (i.e., the external inclined ramp 4 extends vertically from the first layer to the Nth layer of the ore body), and it is ensured that each horizontal inter-layer connecting passage 5 constructed perpendicular to the strike of the ore body from the external inclined ramp 4 corresponds to a random stope 1 (the stope 1 corresponding to each horizontal inter-layer connecting passage 5 is not in the same vertical direction). The horizontal inter-layer connecting passages 5 of each layer are kept horizontal, parallel to each other, and of equal length.

[0060] The preset slope of the external inclined ramp 4 is determined based on the width of stope 1 and pillar 2, as well as the height of each of the N layers divided in step S1. Specifically, when the vertical height of the external inclined ramp 4 decreases by one mining height, its horizontal length extends along the ore body along the strike of the ore body by the sum of the widths of stope 1 and pillar 2. That is, assuming the angle between the external inclined ramp 4 and the horizontal plane is θ, then...

[0061]

[0062] Where H is the height of each layer;

[0063] L1 is the width of each chamber;

[0064] L2 is the width of each pillar.

[0065] This operation only requires setting up a specific external slope 4, and then directly mining several ore rooms 1 in each layer by constructing the horizontal layer-changing connecting road 5 for each layer. This greatly reduces the amount of preparation work and enables rapid mining of ore rooms 1.

[0066] S3. Mining the first stope:

[0067] From the external inclined ramp 4, perpendicular to the ore body, construct the first layer horizontal interchange connecting passage 5 to the footwall 3. At this point, the first layer horizontal interchange connecting passage 5 is directly opposite a stope 1 within the first layer. Continue excavating from the stope 1 corresponding to the first layer horizontal interchange connecting passage 5 to the hanging wall 6, i.e., excavation. Figure 1 From point 1-1 to point 6 on the upper plate.

[0068] At point 6 on the hanging wall, the hanging wall vein 7 is excavated along the strike of the ore body until both sides of the ore body are reached. Support is provided as mining progresses. The dip angle of the hanging wall 6 sidewalls is the same as the dip angle of the ore body, and the dip angle of the hanging wall vein 7 is also the same as the dip angle of the ore body. Therefore, the hanging wall vein 7 has a parallelogram cross-section along the strike of the ore body. Next, from the hanging wall 6 to the footwall 3, the remaining stopes 1 in the first layer are excavated to a predetermined distance from the footwall 3, preferably 3 meters. In practice, when the hanging wall vein 7 reaches a stope 1, excavation of that stope 1 can begin from the hanging wall 6 to the footwall 3. That is, except for the first pillar 1, the remaining pillars 1 can be excavated simultaneously to improve mining efficiency.

[0069] A polyurethane cutting shaft 11 is fixed at the central axis of pillar 2 on the side of the hanging wall 6 away from the hanging wall 6 along the vein 7. The polyurethane cutting shaft 11 extends to the bottom plate of the hanging wall 7 at both ends, and the polyurethane cutting shafts 11 in the upper and lower layers of the hanging wall 7 are interconnected. The polyurethane cutting shaft 11 is made of polyurethane foam material and serves as a cutting shaft to form a compensation space. Figure 3 As shown, a filling retaining wall 12 is set up 3m away from the footwall of the first stope 1 being excavated (that is, the distance of the remaining stopes 1 in this layer from the footwall 3). All the stopes 1 in the first layer are filled, that is, the first stope 1 is filled to a distance of three meters from the footwall 3, and the remaining stopes 1 are completely filled. Then the vein 7 along the hanging wall is filled.

[0070] In this process, the support structure along the upper plate 7 includes upper plate anchor cables 13 installed in the upper plate 6 rock strata, chain link mesh 14 installed on the sidewalls of the upper plate 7, and hanging rods 15 vertically installed in the upper plate 7. Specifically, such as Figures 8 to 9 As shown, the following steps are included in the support and maintenance of the upper plate along vein 7 during mining:

[0071] S31. As the upper hanging wall vein 7 is constructed along both sides of the ore body, upper hanging wall anchor cables 13 perpendicular to the upper hanging wall 6 are constructed in the rock strata of the upper hanging wall 6; the length of the upper hanging wall anchor cables 13 is 2 to 4 m, and the spacing between rows is 1 to 3 m, preferably 3 m long and 2 m apart.

[0072] S32. Fix the chain link mesh 14 on the side of the upper plate along the vein 7 away from the upper plate 6.

[0073] S33. After the stope 1 is filled, vertical lifting bars 15 are installed in the hanging wall 7. During the vertical installation of the lifting bars 15, one end is preferentially connected to the hanging wall anchor cable 13 or a false roof, and the other end is connected to the chain link mesh 14 or a false roof (the false roof refers to the false roof after the lower hanging wall 7 is filled; in actual work, the lower hanging wall 6 has not yet been mined, so a connection point can be reserved. When filling the lower hanging wall 7, the lifting bars 15 in the upper and lower filling bodies can be connected). The lifting bars 15 are 5mm diameter round steel. Because the false roof of the hanging wall 7 is on the side away from the hanging wall 6, it will lose its supporting force as the pillar 2 is mined, causing the false roof of the hanging wall 7 to become unstable, posing a risk of filling body collapse. Therefore, before filling, the false roof needs to be connected to the hanging wall anchor cable 13 using lifting bars 15 to provide traction and fixation for the filling false roof. At the same time, after the upper anchor cable 13 is connected to the chain link mesh 14, its stability is maintained after exposure.

[0074] The polyurethane cutting shaft 11 is cylindrical in shape, and its inclination angle is the same as that of the ore body. The polyurethane cutting shaft 11 can be used as a cutting shaft in the medium-deep hole stope during the mining of pillar 2, to compensate for the compensation space of the medium-deep hole ore falling.

[0075] like Figure 10 As shown, before backfilling, chain link mesh 14 is fixed on both sides of stope 1. Simultaneously, several connecting bars 18 are installed at the horizontal centerline of the chain link mesh 14 on both sides to connect them. That is, the connecting bars 18 are evenly spaced along the ore body strike within stope 1 to ensure the stability of the backfill body after exposure during the second-stage pillar mining, thus reducing the dilution rate. The connecting bars 18 are 5mm diameter steel bars. Furthermore, when laying the false roof on the bottom slab of stope 1, it is fixed to the adjacent pillars 2 on both sides.

[0076] S4. Mining the second to (N-1)th stope layers:

[0077] Repeat step S3 to mine and fill the ore chambers of layers 2 to (N-1) using the down-pass filling mining method. The difference is that the ore chamber 1 of each layer is mined and filled up to the footwall 3.

[0078] S5. Mining the Nth stope:

[0079] Repeat step S3 to mine and fill the Nth layer of ore chamber 1.

[0080] S6. Mining the first pillar:

[0081] like Figure 5 As shown, at the footwall 3 of the first layer, the footwall vein 8 is excavated along the ore body strike until both sides of the ore body are reached. The width of the footwall vein 8 is equal to the preset distance in step S3, preferably 3m. Then, the pillar 2 is excavated perpendicular to the ore body strike from the footwall vein 8, forming the drilling roadway 9. Multiple pillars 2 can be mined simultaneously to improve mining efficiency.

[0082] S7. Mining the Nth pillar:

[0083] Repeat step S6 to excavate pillar 2 of the Nth layer, forming the ore extraction roadway 10. (Example:) Figure 6 As shown, the difference lies in that, at the center line of pillar 2 at point 8 on the lower plate, the ore extraction roadway 10 is excavated to the upper plate 6. Only the middle part of pillar 2 in the Nth layer is mined, with the two sides reserved to support the ore body above. The mining width of pillar 2 in the Nth layer is 2.5 to 3.5m, preferably 3m. At this time, the ore extraction roadway 10 has a size of 3m × 3m (width × height).

[0084] S8. Mining the pillars of layers 2 to (N-1):

[0085] like Figure 7 As shown, mining pillar 2 proceeds simultaneously from layer 2 and layer (N-1) towards each other; after mining is completed, all pillars 2 are then backfilled. The specific steps include the following:

[0086] S81. The vertical strike of the ore body divides each pillar 2 into M columns from the hanging wall 6 to the footwall 3;

[0087] S82. Set blast holes on the upper and lower sides of the first column respectively, and excavate simultaneously in opposite directions; after the excavation is completed, excavate the second column, until the Mth column is reached; the ore pillars 2 set at intervals are mined simultaneously, that is, multiple rows of blast holes can be used to blast from the upper plate 6 to the lower plate 3 in sequence, and rock drilling and blasting can be carried out at the same time to extract ore.

[0088] Specifically, in the upper drilling tunnel 9, downward parallel medium-deep holes 17 are constructed, parallel to the hanging wall 6 of the ore body. Pre-placed polyurethane foam material along the hanging wall 7 serves as the cutting shaft for blasting, forming a cutting groove. Simultaneously, in the lower ore extraction tunnel 10, upward fan-shaped medium-deep holes 16 are constructed. First, pre-placed polyurethane foam material along the hanging wall 7 is used as compensation space, serving as the cutting shaft for blasting, forming a cutting groove. The blast holes in both the drilling tunnel 9 and the ore extraction tunnel 10 are detonated simultaneously to facilitate ore extraction in the lower ore extraction tunnel.

[0089] After the ore is completely removed from the stope, an artificial false bottom is laid on the floor of the ore extraction roadway 10. The reinforcing steel of the false bottom overlaps with the reinforcing steel of the artificial false bottom in the stope 1, forming a unified false bottom. After laying the artificial false bottom, backfilling is carried out. A backfilling wall 12 is erected at the footwall 3 corresponding to the ore extraction roadway 10. Backfilling grout is injected through the drilling roadway 9. Water is drained using the lower backfilling wall 12 for filtration and the pumps in the upper drilling roadway 9 for pumping. The ore block mining is completed after backfilling is finished.

[0090] In summary, the present invention provides a combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on the upper support of the ore body. This method can effectively support the upper body of the ore body in a diversified manner. Simultaneously, the use of downward approach mining in the stope ensures the stability of the approach roof and the filling bodies on both sides. The use of medium-deep hole caving for the pillars, along with the pre-installed polyurethane foam material serving as the cutting shaft, greatly improves mining efficiency. The inclined ramp also serves as a development and preparation engineering facility, effectively reducing the amount of tunneling work, shortening the mining preparation time, and improving mining efficiency, thus possessing extremely high value for widespread application.

[0091] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for coordinated mining based on top support, including downward approach filling and subsequent filling in the medium-deep hole stage, characterized in that... The ore body is inclined, and the hanging wall is fractured; Includes the following steps: S1. Divide the ore body into several blocks along the strike of the ore body, and mine the blocks as units; within each block, divide it into stops and pillars at intervals perpendicular to the strike of the ore body, and divide the block into N layers from top to bottom; S2. Construct an external inclined ramp with a preset slope along the strike of the ore body on the footwall side; the vertical height of the external inclined ramp is equal to the height of the ore block, and ensure that each horizontal connecting road constructed perpendicular to the strike of the ore body from the external inclined ramp corresponds to a random stope. S3. From the inclined ramp outside the vein, construct the first layer of horizontal layer-changing connecting road perpendicular to the ore body to the footwall; continue excavating the stope corresponding to the first layer of horizontal layer-changing connecting road to the hanging wall; at the hanging wall, excavate along the vein of the hanging wall until both sides of the ore body, supporting as mining progresses; from the hanging wall to the footwall, excavate the remaining stopes in the first layer to a predetermined distance from the footwall and then fill them; the first stope excavated is filled to a predetermined distance from the footwall; before filling, fix a polyurethane cutting shaft as a compensation space at the central axis of the pillar on the side of the vein away from the hanging wall; S4. Repeat step S3, and use the down-pass filling mining method to mine and fill the ore rooms of layers 2 to (N-1), and mine and fill the ore rooms of each layer to the lower plate. S5. Repeat step S3 to mine and fill the Nth layer of the ore cell; S6. At the footwall of the first layer, the footwall vein is excavated along the ore body direction until both sides of the ore body are reached, and the width of the footwall vein is equal to the preset distance in step S3; then the pillar is excavated from the footwall vein perpendicular to the ore body direction. S7. Repeat step S6 to excavate the pillar of the Nth layer. The middle part of the pillar of the Nth layer is mined, and the two sides are reserved to support the ore body above. S8. Simultaneously mine the pillars from the 2nd layer and the (N-1)th layer in opposite directions; after mining is completed, fill all the pillars together. Step S8 is as follows: S81. The vertical strike of the ore body divides each of the ore pillars into M columns from the hanging wall to the footwall; S82. Set blast holes on the upper and lower sides of the first column respectively, and excavate simultaneously in opposite directions; after the excavation is completed, excavate the second column, until the Mth column is reached; The pillars, which are spaced apart, are mined simultaneously.

2. The method of coordinated mining based on upper support for downward approach filling and subsequent filling in the medium-deep hole stage, as described in claim 1, is characterized in that... In step S2, the length of the horizontal connecting passage for each layer is equal; the angle between the external ramp and the horizontal plane is θ, where H is the height of each layer; ； L1 is the width of each chamber; L2 is the width of each pillar.

3. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support as described in claim 1, characterized in that, In step S3, the polyurethane cutting well is cylindrical in shape; the inclination angle of the polyurethane cutting well is the same as the dip angle of the ore body.

4. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support as described in claim 1, characterized in that, In step S3, the support structure along the upper plate includes upper plate anchor cables installed in the upper plate strata, chain link mesh installed on the sidewall of the upper plate, and hanging rods installed vertically along the upper plate.

5. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support according to claim 4, characterized in that, In step S3, the support along the upper plate during mining includes the following steps: S31. As the upper plate is constructed along the vein, upper plate anchor cables perpendicular to the upper plate are constructed in the rock strata of the upper plate; S32. Fix the chain link mesh on the side of the upper plate away from the upper plate along the vein; S33. Vertical suspension rods are provided along the vein of the upper plate; the suspension rods, the upper plate anchor cable, and the chain link mesh are interconnected.

6. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support according to claim 1, characterized in that, The blasting was carried out using an upward fan-shaped medium-deep hole method at the bottom and a downward parallel medium-deep hole method at the top.

7. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support according to claim 4, characterized in that, Before the mine is filled, the chain link mesh is fixed on both sides; several suspension rods are used to connect the chain link mesh on both sides at the center line of the two sides.

8. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support according to claim 1, characterized in that, The width of the stope is 4-6m, and the width of the pillar is 9-11m; in step S7, the mining width of the pillar in the Nth layer is 2.5-3.5m.

9. The combined mining method of downward approach filling and subsequent filling in the medium-deep hole stage based on upper support according to claim 1, characterized in that, The ore block is 110-120m wide and 25-35m high; the ore block is divided into 10 layers from top to bottom, with each layer being 2.5-3.5m high.

Images