A mining method of large-diameter deep hole subsequent filling without pull bottom fan

Abstract

The application discloses a large-diameter deep-hole subsequent filling mining method without a pull bottom fan, and belongs to the technical field of underground metal mine exploitation. The method comprises the following steps: preparing a stope and arranging a pull bottom structure, constructing an upper rock drilling roadway, a lower ore receiving roadway and a mine outlet structure, pre-supporting, forming an end cutting groove, constructing a fan-shaped deep hole along the rock drilling roadway to the ore receiving roadway and correcting the hole by hole, manually hoisting and spacing the charge in the cavity at the bottom of the hole, initiating the bottom of the hole, and filling the hole mouth, initiating the cutting groove hole first and then performing differential blasting by row, ventilating and discharging the ore, and cyclically correcting, finally mining and subsequently filling, wherein the hole is blocked by a blocking piece and a suspension rope, a detonating cord is laid in the charging section, and the holes are initiated in an approximate V-shaped sequence.

Description

Technical Field

[0001] This application relates to the field of mining, and in particular to a method for subsequent backfilling of large-diameter deep holes in a fan-shaped structure without bottoming. Background Technology

[0002] Steeply dipping thin ore bodies typically exhibit characteristics such as small horizontal thickness, large dip angle, and rapid changes in morphology along the strike and dip. When the ore body is simultaneously affected by faults, joints, alteration zones, or groundwater and is in a fractured state, the exposed roof and hanging wall are prone to spalling, caving, and local instability. Although the traditional shallow-hole upward layered backfilling method can selectively mine along the ore body boundaries, it involves multiple cycles of preparation, layering, ore extraction, and backfilling, resulting in long working hours for personnel and equipment below the exposed surface of the stope, thus limiting production capacity and mechanization levels.

[0003] The large-diameter deep-hole stage open-hole subsequent backfilling method allows personnel to be mainly stationed in the supported drilling and ore-extraction roadways, offering advantages such as high mechanization, relatively less mining and cutting work, and concentrated production. However, existing large-diameter deep-hole schemes typically still require the construction of bottom-pull roadways at the bottom of the stope, using upward medium-deep or shallow holes to pre-create bottom-pull spaces, trenches, or bottom compensation spaces before conducting lateral caving with large-diameter deep holes from above. For fractured thin ore bodies, the bottom-pull space itself is difficult to maintain, and bottom-pull blasting requires workers to repeatedly drill, load explosives, and handle loose rocks near the unstable bottom structure, resulting in significant safety risks and a large workload. Summary of the Invention

[0004] To reduce bottom excavation, equipment relocation, and repetitive support work, this application provides a bottom-pull-free, fan-shaped, large-diameter deep-hole subsequent backfilling mining method.

[0005] This application provides a method for mining large-diameter deep holes with no bottom pull and subsequent backfilling, which adopts the following technical solution:

[0006] A method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming includes the following steps:

[0007] S1. Mining preparation and layout of non-pull-bottom structure: Determine the mining boundary, construct rock drilling roadways along the upper part of the mining area, and construct flat-bottom receiving roadways, ore extraction roadways and ore extraction access roads in the lower part. Do not construct continuous pull-bottom roadways along the strike.

[0008] S2, Advanced Support: Support for rock drilling tunnels and fractured surrounding rock;

[0009] S3. Forming an end cutting groove: Forming a cutting groove at the end of the stope that connects to the lower ore-receiving area;

[0010] S4. Construction of fan-shaped deep holes and rolling borehole measurement: Construct large-diameter fan-shaped deep holes downwards along the rock drilling tunnel to the ore receiving tunnel, determine the parameters of each hole, and measure and revise the charging plan for each hole.

[0011] S5. Charging and detonation: Explosives are placed into the borehole and the borehole opening is filled. A detonating charge is placed at the bottom of the borehole and detonated from the bottom.

[0012] S6. Row-by-row micro-differential blasting: First, detonate the cutting slot to form a cavity that connects with the receiving roadway, and then detonate the main row of blast holes row by row with the cutting slot as the free surface.

[0013] S7. Ventilation, Ore Extraction and Cycle Correction: After blasting, ventilation is checked and ore is extracted from the ore extraction route. The compensation space is checked and the parameters for the next cycle are corrected based on the blast volume and ore extraction volume.

[0014] S8. Final mining and subsequent backfilling: After all mining is completed, the remaining ore is recovered, the goaf is sealed, and subsequent backfilling is carried out.

[0015] The blast holes adopt a cavity-spaced charge structure at the bottom, and the bottom of the holes is sealed with plugging parts and suspension ropes. The entire length of the charge section is covered with detonating cord. The blasting sequence of the main row of blast holes is from the center of the row to both sides, and the blast holes closest to the ore boundary are detonated last.

[0016] Optionally, in S1, the mining area is arranged along the strike of the ore body, with little or no top or bottom pillars; the ore extraction roadway is set every 8 to 15 meters, with an angle of 40° to 60° with the ore extraction roadway; the rock drilling roadway and the ore receiving roadway are directly connected by cutting slots and blast holes, without reserving a rock bridge above the roof of the ore receiving roadway.

[0017] Optionally, in S2, for the fault fracture zone of the hanging wall of the ore body, anchor cable chambers are set at intervals along the drilling roadway, and medium and long anchor cable holes are constructed from the anchor cable chambers to the hanging wall and grouted for anchoring; before the first blasting unit is implemented, baseline checks are carried out on the roadway convergence, anchor bolt anchoring, shotcrete cracking and steel arch deformation, and are reviewed after each blast.

[0018] Optionally, in S3, a cutting cross passage and a cutting riser are set at the end of the stope. After the cutting riser is formed, parallel holes or fan-shaped holes are constructed in the cutting cross passage to expand the groove. Alternatively, a cutting passage with partial roof tilting or expansion is set at the end of the stope. Using this space as a free surface, dense small-row fan-shaped holes are used to form a full-section cutting groove by blasting at different angles and in stages. After the cutting groove is formed, the groove cavity is judged to have reached the design height and width by observation holes, boreholes, laser ranging, blast pile elevation measurement, or ore output back calculation.

[0019] Optionally, in S4, the diameter of the blast hole in the fan-shaped large-diameter deep hole is 0.08–0.12 m, the row spacing of the blast holes is 1.6–2.2 m, the hole spacing is 1.8–2.6 m, and the minimum resistance line is 1.8–2.4 m; the row spacing of the blast holes near the end cutting groove is 0.8–1.2 m, and the hole spacing is 1.0–1.6 m; the over-depth correction of the blast hole is 0–0.8 m.

[0020] Optionally, in S4, the stope is divided into blasting units of 2-5 rows of blast holes each time, and only the current blasting unit and the next backup unit are drilled. After each hole is completed, the hole depth, azimuth and dip angle are measured. When the actual connection position of the blast hole with the receiving roadway deviates from the design position but still enters the receiving roadway and the hole body is located in the ore body, the charge length is corrected according to the measured hole depth. When the blast hole deviates into the surrounding rock, does not enter the receiving roadway or the distance between the blast hole and the adjacent blast hole is too large, the charge amount is reduced, the charge section is shortened, the hole is changed to an empty hole or a small-angle supplementary hole is used in the same row. When the blast hole collapses, the blast hole construction continues according to the original design at 0.5m intervals. A single hole record is established for each blast hole, including design parameters, construction parameters, hole measurement results, abnormal locations, treatment measures and final charge plan.

[0021] Optionally, in S5, 2-3 strips of base charge are placed at the bottom of each borehole before the detonating charge is lowered; the interval section uses a bamboo tube with a length of 1m and a diameter of 70-80mm; the bottom of the borehole is sealed with a cement plug and a steel wire rope suspension; each borehole is equipped with a double electronic detonator, which is placed inside a detonating charge made of a detonating cartridge case; the borehole opening is filled with stemming clay or fine sand, with a filling length of 1.5m; before loading the charge, the water accumulation in the borehole, the plugging of the borehole, and the sealing status of the bottom of the borehole are checked. If there is water accumulation, explosives and detonating charges suitable for the water environment are selected, or the water is drained and the borehole is blown out first.

[0022] Optionally, in S6, the delay time between adjacent blast holes is 20-50ms; the approximate V-shaped blasting unfolds from the blast holes near the center of the row with good compensation conditions to both sides, and the blast holes in the row of blast holes near the boundaries of the upper and lower footwalls are detonated last; a single blasting involves 2-5 rows of blast holes, and the number of rows in a single blasting is reduced when the blast holes are severely confined.

[0023] Optionally, in S7, the ore loosening coefficient after blasting is 1.30 to 1.60, and the compensation space safety factor is 1.05 to 1.30. The compensation space is checked based on the original rock volume of the blasting unit, the available space of the cutting groove, the available space of the receiving roadway, the blast pile gap, and the controlled ore output, and the number of blasting rows and the ore output are determined accordingly.

[0024] Optionally, in S8, filling retaining walls are installed in the receiving roadway, the exit roadway, and other roadways connected to the goaf, and subsequent filling is carried out through the upper filling connecting roadway and filling pipeline; higher strength cemented filling material is used at the bottom and top of the goaf, and lower strength cemented filling material is used in the middle.

[0025] In summary, this application includes the following beneficial technical effects:

[0026] 1. Eliminate bottom-running and reduce mining and cutting work. This application does not construct bottom-running roadways extending along the bottom of the mining area, and does not include medium-deep hole bottom-running drilling, charging and blasting procedures, which can reduce the amount of bottom excavation, equipment relocation and repeated support work.

[0027] 2. Adaptable to thin ore bodies and irregular boundaries. The orientation, dip angle, depth, and penetration position of the fan-shaped holes are aligned with the upper and lower boundaries of the ore body, the lower boundary, and the outline of the receiving roadway. It is not required to expand the mining width to arrange parallel holes. When there is local thinning, curvature, or misalignment between the upper and lower middle sections, the hole angle, hole length, and boundary inward reduction can be adjusted.

[0028] 3. Complete closed-loop process. The design of the perforation grid, charging, detonation, ore extraction, compensation space restoration and subsequent filling are mutually constrained and can be modified cyclically according to the actual blast pile and boundary effects, which is convenient for field implementation and promotion. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the mining method of the present invention;

[0030] Figure 2 for Figure 1 Section II-II;

[0031] Figure 3 for Figure 1 Section III-III;

[0032] Figure 4 for Figure 2 Section IV-IV;

[0033] Figure 5 This is a schematic diagram of the support at the bottom of the hole.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Lower-middle section ore extraction roadway; 2. Ore extraction cross-cut; 3. Ore receiving roadway; 4. Drilling chamber; 5. Cutting riser; 6. Blasting hole; 7. Blasting pile; 8. Anchor cable chamber; 9. Anchor cable; 10. Mine pillar; 11. Borehole filling section; 12. Interval section; 13. Charging section; 14. Borehole bottom support; 15. No. 8 steel wire; 16. Concrete; 17. Wooden stick. Detailed Implementation

[0036] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0037] This application provides a non-bottom-drawing fan-shaped large-diameter deep-hole subsequent backfilling mining method. "Non-bottom-drawing" in this application means: no upward-facing medium-deep bottom-drawing holes are constructed to form a continuous bottom-drawing space through the stope, and no pre-blasting is performed to form a continuous bottom-drawing space before the formal mining of the large-diameter deep-hole. Non-bottom-drawing is not equivalent to having no bottom ore extraction structure; this application can still set up flat-bottomed receiving roadways, ore extraction roadways, and ore extraction entrances at the bottom, and can set up cutting risers at the end of the stope or use non-cutting fan-shaped holes to form the initial cutting groove;

[0038] Taking the recovery project of a fractured, steeply dipping, thin ore body in an underground metal mine as an example, the ore body is approximately vertical with a horizontal thickness of about 5m, a stope length of about 50m along the strike, and a stage height of about 40m. The method includes the following steps:

[0039] S1. Stope preparation and layout of the non-basement structure:

[0040] Obtain data on the exposure of exploration roadways, production boreholes, structural logging, and rock mass quality in the upper and lower middle sections, and establish a three-dimensional model of the ore body. Select ore sections with high overlap between their upper and lower projections along the strike as large-diameter deep-hole stopes; delineate non-overlapping sections into boundary control zones or use local shallow-hole recovery methods. The stopes are arranged along the strike of the ore body, with minimal or no top and bottom pillars; the length, width, and height of the stopes are determined based on the ore body morphology, the effective hole depth of the drilling equipment, and the stability of the stopes.

[0041] The upper middle section of the stope is constructed with rock-drilling tunnels, while the lower middle section is constructed with flat-bottomed receiving tunnels, vein-exiting tunnels, and ore-exiting access tunnels. The receiving tunnel is located at the footwall boundary or bottom of the ore body, and its shape is controlled by the length and location of the blast holes, forming a bottom receiving edge that slopes towards the receiving tunnel. No continuous bottom-pull tunnels are constructed along the strike of the entire stope, and no independent bottom-pulling rock layers are set up. The upper rock-drilling tunnels and the lower receiving tunnel are directly connected by cutting slots and main-row blast holes. The blast holes extend to the receiving tunnel, and no rock bridges requiring blasting are left above the roof of the receiving tunnel.

[0042] In this embodiment, the upper middle section was originally planned to form a wider drilling chamber, but due to local fault fracturing, a drilling tunnel of about 3.0m×3.3m was actually arranged; the lower section is arranged with a flat-bottomed ore receiving tunnel of about 4.0m×3.0m, an ore exit tunnel of about 2.8m×2.8m and multiple ore exit routes, and no bottom-pulling tunnel is arranged.

[0043] S2, Advanced Support:

[0044] To enhance construction safety, small-section drilling roadways are used, sufficient only to accommodate equipment passage. For the fault fracture zone in the hanging wall of the ore body, anchor cable chambers are installed at intervals along the drilling roadway. Medium-length anchor cable holes are drilled from these chambers towards the hanging wall and grouted for anchoring. Large-diameter deep-hole drilling can only commence after the support is completed and reaches its design strength. The drilling roadway support should be compatible with the vibration conditions of deep-hole blasting. Before the first blasting unit, baseline checks are conducted on roadway convergence, anchor bolt anchoring, shotcrete cracking, and steel arch deformation, and these checks are repeated after each blast. For areas with concentrated blast hole openings, localized steel or reinforced concrete reinforcement strips are installed. If significant failure of the support components is found, the roadway's load-bearing and protective capacity should be restored before proceeding with the next cycle of charging and blasting.

[0045] S3. Form the end cutting groove:

[0046] Cutting crossroads and cutting risers are set up at the end of the stope. After the cutting risers are formed, parallel holes or fan-shaped holes are constructed in the cutting crossroads to widen the groove, so that the cutting groove covers the planned mining area and connects with the lower ore receiving area. If it is difficult to form a riser in the fractured ore body, a locally overhanging or enlarged cutting crossroads are set up at the end of the stope. Using this space as a free surface, dense small-spaced fan-shaped holes are used to form a full-section cutting groove by blasting at different angles and in stages.

[0047] After the cutting groove is formed, the usable volume and connectivity should be inspected. The groove cavity should be judged to have reached the design height and width by observation holes, drilling, laser ranging, blast pile elevation measurement or ore output calculation. If the groove cavity is partially confined, the bottom is not connected to the ore receiving space, or the blast pile is blocked, the groove cavity should be restored by filling holes, local small-scale explosive treatment or controlling ore output. It is not advisable to directly detonate large-scale mining blast holes.

[0048] In this embodiment, the cross-section of the well is approximately 1.6m × 1.6m.

[0049] S4. Sector-shaped deep hole construction and rolling borehole measurement:

[0050] Drilling stations are set up along the drilling roadway at row spacing, with each station drilling a row of large-diameter, fan-shaped deep holes downwards. Cutting slot holes and main row blast holes are drilled downwards from the upper drilling roadway to the receiving roadway. The azimuth, dip angle, hole depth, and connection position of each row of blast holes are determined hole-by-hole based on the upper and lower boundaries of the ore body within that row's profile, the outline of the receiving roadway, and the position of the end cutting slot. Cutting slot holes use a smaller row spacing and connection position interval to form a cavity that covers the mining area and connects to the receiving roadway after detonation. Main row blast holes cover the entire height of the ore body and are arranged row by row along the strike of the stope, with the cutting slot as the free surface.

[0051] The stope is divided into blasting units of 2-5 rows of boreholes each time. Only the current blasting unit and the next backup unit are drilled; the entire stope is not drilled at once. After each borehole is completed, the depth, azimuth, and dip angle are measured. When the actual connection position of the borehole to the receiving roadway deviates from the design position but still enters the receiving roadway and the borehole body is within the ore body, the charge length is adjusted according to the measured depth. When the borehole deviates into the surrounding rock, does not enter the receiving roadway, or the distance between adjacent boreholes is too large, the charge amount is reduced, the charge section is shortened, the borehole is converted to an empty borehole, or a small-angle supplementary borehole is used in the same row. When a borehole collapses, borehole construction continues according to the original design at 0.5m intervals. A single-hole record is established for each borehole, including design parameters, construction parameters, borehole measurement results, abnormal locations, handling measures, and the final charge plan. The allowable value for borehole deviation is not uniformly set for all ore sections, but is based on a comprehensive criterion: whether the borehole crosses the ore-rock boundary, whether it connects to the receiving roadway, and whether it causes excessive distance between adjacent boreholes.

[0052] In this embodiment, a down-the-hole drill rig is used to drill cutting slots and main blast holes downwards from the upper single rock drilling tunnel. Both the cutting slots and main blast holes penetrate to the receiving tunnel. The blast hole diameter is approximately 90mm, the spacing of the main blast holes is approximately 2.0m, and the spacing at the point of penetration in the receiving tunnel is approximately 2.0 to 2.4m; the spacing of the cutting slots is approximately 1.0m, and the spacing at the point of penetration in the receiving tunnel is approximately 1.4m.

[0053] S5. Charge and Detonation:

[0054] Both the cutting slot holes and the main row blast holes are manually loaded with explosives using a hollow cavity structure at the bottom of the holes. All blast hole bottoms are sealed with cement plugs and steel wire ropes for suspension, while the hole openings are filled with stemming clay or fine sand for a length of 1.5m. All blast holes are detonated from the bottom, with each hole equipped with two electronic detonators placed inside an initiating charge made from a detonating cartridge case. Before lowering the initiating charge, 2-3 strips of base charge are placed at the bottom of the hole. Detonating cord is laid along the entire length of the blast hole, with intervals using bamboo tubes 1m long and 70-80mm in diameter. Before loading, the condition of any water accumulation, hole plugging, and bottom sealing in the hole is checked. If water accumulation is present, explosives and initiating charges suitable for the aquatic environment are selected, or the water is drained and the hole is bleed out first.

[0055] S6, sequential micro-delay blasting:

[0056] First, the cutting slots are detonated to form a cutting slot that extends through the ore body to the mining height and connects to the receiving roadway. After the cutting slot is formed, the first row of main blast holes is detonated with the slot cavity as the free surface. The blasting adopts an approximately V-shaped blasting method, starting from the blast holes near the center of the row and with better compensation conditions, and expanding to both sides. The main blast holes near the ore-rock boundaries of the hanging wall and footwall are detonated last. A single blasting operation consists of 2 to 5 rows of main blast holes; when the blast holes are severely congested, the number of rows per blasting operation is reduced.

[0057] In this embodiment, the delay time between adjacent blast holes is approximately 35ms. The first blast consists of two rows of blast holes in a straight line. After the ore is extracted and the compensation space is restored, subsequent blasts consist of approximately five rows each.

[0058] S7, Ventilation, Ore Production and Cycle Correction:

[0059] After blasting, fresh air is introduced through the lower transport roadway and the ore exit roadway, while contaminated air is discharged through the cutting groove, the upper drilling roadway, and the return air system. After the blasting fumes are cleared and the roof, roadways, and blockage conditions are checked, the shoveling and transporting equipment exits the ore through the ore exit roadway from the flat-bottom receiving roadway.

[0060] The available compensation space for the next cycle is calculated based on the actual ore collapse volume, loosening coefficient, and ore output of the current ore collapse.

[0061] In this embodiment, a shovel and transport device of approximately 1 m³ is used to transport ore from the ore exit entrance.

[0062] S8. Final extraction and subsequent filling:

[0063] After all blasting units have been mined, remote-controlled shovels are used to recover residual ore and clear the main ore receiving passages. Subsequently, backfill retaining walls are installed in the receiving roadways, exit roads, and other roadways connecting to the goaf, and backfilling is carried out through upper backfill connecting passages and backfill pipelines. Higher-strength cemented backfill material is used at the bottom and top of the goaf, while lower-strength cemented backfill material is used in the middle. After the backfill material reaches its design strength, adjacent stopes are then mined.

[0064] The above results indicate that the fan-shaped deep hole and flat-bottom ore extraction structure can complete the mining without setting up an independent bottom haulage roadway and a medium-deep hole bottom haulage process.

[0065] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for mining large-diameter deep holes without bottoming and subsequent backfilling, characterized in that, Includes the following steps: S1. Mining preparation and layout of non-pull-bottom structure: Determine the mining boundary, construct rock drilling roadways along the upper part of the mining area, and construct flat-bottom receiving roadways, ore extraction roadways and ore extraction access roads in the lower part. Do not construct continuous pull-bottom roadways along the strike. S2, Advanced Support: Support for rock drilling tunnels and fractured surrounding rock; S3. Forming an end cutting groove: Forming a cutting groove at the end of the stope that connects to the lower ore-receiving area; S4. Construction of fan-shaped deep holes and rolling borehole measurement: Construct large-diameter fan-shaped deep holes downwards along the rock drilling tunnel to the ore receiving tunnel, determine the parameters of each hole, and measure and revise the charging plan for each hole. S5. Charging and detonation: Explosives are placed into the borehole and the borehole opening is filled. A detonating charge is placed at the bottom of the borehole and detonated from the bottom. S6. Row-by-row micro-differential blasting: First, detonate the cutting slot to form a cavity that connects with the receiving roadway, and then detonate the main row of blast holes row by row with the cutting slot as the free surface. S7. Ventilation, Ore Extraction and Cycle Correction: After blasting, ventilation is checked and ore is extracted from the ore extraction route. The compensation space is checked and the parameters for the next cycle are corrected based on the blast volume and ore extraction volume. S8. Final mining and subsequent backfilling: After all mining is completed, the remaining ore is recovered, the goaf is sealed, and subsequent backfilling is carried out. The blast holes adopt a cavity-spaced charge structure at the bottom, and the bottom of the holes is sealed with plugging parts and suspension ropes. The entire length of the charge section is covered with detonating cord. The blasting sequence of the main row of blast holes is from the center of the row to both sides, and the blast holes closest to the ore boundary are detonated last.

2. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S1, the mining area is arranged along the ore body strike, with little or no top or bottom pillars; the ore extraction roadway is set every 8 to 15 m, with an angle of 40° to 60° with the ore extraction roadway; the rock drilling roadway and the ore receiving roadway are directly connected by cutting slots and blast holes, without reserving a rock bridge above the roof of the ore receiving roadway.

3. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S2, for the fault fracture zone on the hanging wall of the ore body, anchor cable chambers are set at intervals along the drilling tunnel. Medium and long anchor cable holes are constructed from the anchor cable chambers to the hanging wall and grouting is used for anchoring. Before the first blasting unit is implemented, baseline checks are conducted on roadway convergence, anchor bolt anchoring, shotcrete cracking, and steel arch deformation, and these checks are repeated after each blast.

4. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S3, a cutting cross passage and a cutting riser are set at the end of the stope. After the cutting riser is formed, parallel holes or fan-shaped holes are constructed in the cutting cross passage to expand the groove. Alternatively, a cutting cross passage with partial roof tilting or expansion is set at the end of the stope. Using this space as a free surface, a full-section cutting groove is formed by blasting at different angles and in stages with densely spaced fan-shaped holes. After the cutting groove is formed, it is determined whether the groove cavity has reached the design height and width by observing through observation holes, drilling, laser ranging, measuring the elevation of the blast pile, or calculating the ore output.

5. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S4, the diameter of the blast hole in the large-diameter fan-shaped deep hole is 0.08–0.12 m, the row spacing of the blast holes is 1.6–2.2 m, the hole spacing is 1.8–2.6 m, and the minimum resistance line is 1.8–2.4 m; the row spacing of the blast holes near the end cutting groove is 0.8–1.2 m, and the hole spacing is 1.0–1.6 m; the over-depth correction of the blast hole is 0–0.8 m.

6. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S4, the stope is divided into blasting units of 2-5 rows of blast holes each time. Only the current blasting unit and the next backup unit are drilled. After each hole is completed, the hole depth, azimuth, and dip angle are measured. When the actual connection position of the blast hole with the receiving roadway deviates from the design position but still enters the receiving roadway and the hole body is located in the ore body, the charge length is adjusted according to the measured hole depth. When the blast hole deviates into the surrounding rock, does not enter the receiving roadway, or the distance between the blast hole and the adjacent blast hole is too large, the charge amount is reduced, the charge section is shortened, the hole is changed to an empty hole, or a small-angle supplementary hole is used in the same row. When the blast hole collapses, the blast hole construction continues according to the original design at 0.5m intervals. A single hole record is established for each blast hole, including design parameters, construction parameters, hole measurement results, abnormal locations, treatment measures, and the final charge plan.

7. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S5, 2-3 strips of base charge are placed at the bottom of each borehole before the detonating charge is lowered; the interval section is made of bamboo tubes with a length of 1m and a diameter of 70-80mm; the bottom of the borehole is sealed with cement plugs and steel wire ropes for suspension; each borehole is equipped with dual electronic detonators, which are placed inside the detonating charge made of detonating cartridge cases; the borehole opening is filled with stemming clay or fine sand, with a filling length of 1.5m; before loading the charge, the water accumulation in the borehole, the plugging of the borehole and the sealing status of the bottom of the borehole are checked. If there is water accumulation, explosives and detonating charges adapted to the water environment are selected, or the water is drained and the borehole is blown out first.

8. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S6, the delay time between adjacent blast holes is 20-50ms; the approximate V-shaped blasting starts from the blast holes near the center of the row and has good compensation conditions and spreads to both sides, with the main row of blast holes near the boundaries of the upper and lower footwalls being the last to be detonated; a single blasting involves 2-5 rows of main row blast holes, and the number of rows in a single blasting is reduced when the blast holes are severely confined.

9. A method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming, as described in claim 1, is characterized in that... In S7, the ore loosening coefficient after blasting is 1.30 to 1.60, and the compensation space safety factor is 1.05 to 1.

30. The compensation space is checked based on the original rock volume of the blasting unit, the available space of the cutting slot, the available space of the receiving roadway, the blast pile gap, and the controlled ore output, and the number of blasting rows and the ore output are determined accordingly.

10. The method for subsequent backfilling mining of large-diameter deep holes in a fan-shaped pattern without bottoming according to claim 1, characterized in that, In S8, filling retaining walls are installed in the receiving roadway, the exit roadway and other roadways connected to the goaf, and subsequent filling is carried out through the upper filling connecting roadway and filling pipeline; the bottom and top of the goaf are filled with high-strength cemented filling material, and the middle part is filled with low-strength cemented filling material.

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