Vertical deep hole stage ore breaking subsequent filling stope roof contact structure and mining method

Abstract

The invention discloses a vertical deep hole stage ore breaking subsequent filling stope roof-contacted structure and a mining method, ore blocks are arranged along the trend of an ore body, and the ore body is divided into a plurality of continuous chambers which are sequentially divided into a first-step mining chamber and a second-step mining chamber; the ore blocks are divided into a plurality of stages in the vertical direction, and a rock drilling chamber and an undercutting trench roadway are arranged in each stage; filling drill holes are drilled from the undercut trench roadway in the previous stage to the rock drilling chambers of the adjacent chambers in the next stage; a special-shaped top plate is designed above the rock drilling chamber; the special-shaped top plate is in a step shape, the upper table top is located on one side of a filling drill hole discharging opening, and the lower table top is obliquely and downwards diffused to the other side of the rock drilling chamber. The original mining preparation cutting engineering is fully utilized to design filling drill holes, the roof is formed by designing the rock drilling chamber, the roof contact process is simple, the roof contact quality is guaranteed, roof deformation and ground surface settlement can be effectively controlled, construction is easy, and the cost is low.

Description

Technical Field

[0001] This invention relates to the field of mining technology, and in particular to a vertical deep-hole stage ore-cutting subsequent backfilling stope roof support structure and mining method. Background Technology

[0002] Vertical deep-hole staged ore cutting followed by backfilling is an organic combination of backfilling and open-hole mining methods. It offers advantages such as improved mining efficiency, enhanced mine stability, reduced mining costs, increased ore recovery, environmental protection, and strong adaptability. These advantages have led to its widespread application in large and medium-sized mines both domestically and internationally, yielding significant economic and social benefits. This method involves two-step, alternating mining of the block, with the first and second-step stopes spaced alternately. The first-step stop is mined first, followed by cemented backfilling and curing. Then, the second-step stop is mined, followed by non-cemented backfilling. After the cemented backfill slurry from the first step solidifies, it forms a rigid support structure, inhibiting surrounding rock deformation and providing a safe environment for subsequent mining operations. After the non-cemented backfill slurry from the second step solidifies, it alleviates stress concentration and facilitates complete replacement of the ore body. Roofing in the stope is crucial for limiting roof subsidence in the goaf, controlling strata movement, and preventing surface subsidence.

[0003] After the filling slurry enters the stope void from the filling borehole, the spatial effect and consolidation phase change result in a consolidation trajectory surface that is high at the discharge port and low around the perimeter. The forced roof support structure technology is complex, with dispersed action points, extending operation time and increasing construction difficulty. The use of an expansion roof support structure poses a significant safety hazard when the filling material is exposed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a safe, easy-to-construct, and low-cost vertical deep-hole stage ore cutting followed by backfilling stope top structure; the present invention also provides a vertical deep-hole stage ore cutting followed by backfilling stope mining method with small mining and cutting workload and high ore extraction efficiency.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the structure of the present invention is as follows: the ore blocks are arranged along the strike of the ore body, and the ore body is divided into several continuous mining houses, which are successively divided into first-stage mining houses and second-stage mining houses; the ore blocks are divided into several stages along the vertical direction, and drilling chambers and bottom-cutting trenches are arranged in each stage; the bottom-cutting trenches of the previous stage drill filling boreholes to the drilling chambers of the adjacent mining houses of the next stage; an irregular roof plate is designed above the drilling chambers; the irregular roof plate is stepped, with the upper platform located on one side of the filling borehole discharge port, and the lower platform diagonally spreading downward to the other side of the drilling chamber.

[0006] Furthermore, the slope of the lower platform of the irregularly shaped top plate is 3 to 4 degrees.

[0007] Furthermore, the width of the upper platform in the irregularly shaped top plate is 3 to 5 meters.

[0008] Furthermore, the step height of the irregularly shaped roof plate is 1.5 to 2 meters.

[0009] To solve the above technical problems, the method of the present invention adopts the above-mentioned top-connecting structure, and the technical solution adopted includes the following steps: 1) Drilling upward medium-deep blast holes from the bottom trench roadway and drilling downward deep blast holes from the rock-drilling chamber to carry out blasting and caving to extract ore. 2) Indirect mining is used for one-step mining; for two-step mining, one side of the cemented ore chamber is mined first, and then the other side of the cemented ore chamber is mined. 3) After the ore body of the first-stage mining stop is extracted, the goaf is cemented and backfilled; after the ore body of the second-stage mining stop is extracted, the goaf is non-cemented and backfilled. 4) Construction and filling of boreholes in the bottom trench tunnel from the previous stage.

[0010] Furthermore, in step 4), the spacing of the filling boreholes is 40–60 m.

[0011] Furthermore, in step 4), venting boreholes are also constructed, with filling boreholes and venting boreholes spaced apart.

[0012] The beneficial effects of adopting the above technical solution are as follows: This invention takes the filling and cutting engineering of the vertical deep hole stage as the starting point, makes full use of the original filling borehole design of the mining preparation and cutting engineering, and forms an irregular roof plate by designing the rock drilling chamber. The roof connection process is simple, the roof connection quality is guaranteed, it is easy to construct and has low cost. Attached Figure Description

[0013] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0014] Figure 1 This is a cross-sectional view of the vertical deep hole stage of the present invention along the ore body strike; Figure 2 This is a vertical ore body strike profile of the vertical deep hole stage of the present invention; Figure 3 This is a diagram showing the division of cemented and uncemented chambers in the vertical deep hole stage of this invention; Figure 4 This is a diagram of cemented stope filling in the vertical deep hole stage of this invention; Figure 5 This is a diagram showing the filling of the non-cemented stope on the left side of the cemented stope in the vertical deep hole stage of this invention. Figure 6 This is a diagram showing the filling of the non-cemented stope on the right side of the cemented stope in the vertical deep hole stage of this invention. Figure 7 This is a schematic diagram of the shape of the irregular top plate described in this invention.

[0015] In the diagram: 1-Ladi trench roadway, 2-Mining roadway, 3-Drilling chamber pillar, 4-Drilling chamber, 5-Irregular roof, 51-Upper platform, 52-Connecting surface, 53-Lower platform, 6-Filling borehole, 7-Ventilation borehole, L1-Width of first-stage mining stope, L2-Width of second-stage mining stope, h-Height of roof pillar, H-Stage height, L-Width of ore body, Ⅰ-Drilling and blasting area, Ⅱ-Ore pile, Ⅲ-Mining stope void, Ⅳ-Mining stope filling area. Detailed Implementation

[0016] Figure 1-7 As shown, the top structure of the subsequent backfilling stope for this vertical deep-hole stage is as follows: For inclined thick ore bodies or gently inclined thick ore bodies, the ore blocks are arranged along the strike of the ore body, with the horizontal width of the ore block being L. The ore body is divided into several continuous stops, namely, a first-stage stop and a second-stage stop, with the width of the first-stage stop being L1 and the width of the second-stage stop being L2. The ore blocks are divided into several stages along the vertical direction. A drilling chamber 4 is arranged at the upper part of each stage, and a drilling chamber pillar 3 is designed. A bottom trench roadway 1 is arranged at the lower part of each stage. In the previous stage, the bottom-cutting ditch roadway had filling boreholes 6 drilled. These filling boreholes 6 were drilled obliquely downwards to the drilling chamber 4 of the adjacent stope in the next stage, with the discharge port of the filling boreholes 6 located on the side of the drilling chamber 4 in the following direction. The filling boreholes 6 were arranged in rows, several rows along the ore body direction, with each row perpendicular to the ore body direction and the spacing between the filling boreholes 6 being 20-30m. The previous stage also had venting boreholes 7 drilled in the bottom-cutting ditch roadway; these filling boreholes 6 were also arranged in rows, several rows along the ore body direction, with each row perpendicular to the ore body direction and the spacing between the venting boreholes 7 being 20-30m. The rows of filling boreholes and venting boreholes were spaced apart.

[0017] An irregularly shaped roof plate 5 is designed above the rock drilling chamber 4. Figure 7 As shown, the irregular roof slab 5 is stepped, including an upper platform 51, a lower platform 53, and a connecting surface 52 connecting the two. The upper platform is located on the side of the material outlet of the filling borehole 6, that is, on the side of the rock drilling chamber 4 following the direction of the rock drilling chamber 4. The width of the upper platform, that is, the distance from the boundary of the rock drilling chamber 4 following the direction of the rock drilling chamber 4 to the edge of the upper platform, is 3-5m. The lower platform slopes downward at a gradient of 3-4°, extending to the side of the rock drilling chamber 4 following the direction of the rock drilling chamber 4. The step height of the irregular roof slab 5, that is, the vertical height of the connecting surface 52, is 1.5-2m. The location of the material outlet of the filling borehole 6 is located on the intersection line with the adjacent stope, 2-3m above the boundary of the upper platform 51. The stope with the last direction of the rock drilling chamber is constructed with a separate filling roadway, and the irregular roof slab 5 is installed in the filling roadway.

[0018] Figure 1-7As shown, in this vertical deep hole stage, the subsequent backfilling structure of the stope is as follows: the first-stage stope uses cemented backfill with a bottom backfill height of 10-12m and a top backfill height of 4-6m; the second-stage stope uses non-cemented backfill with a bottom backfill height of 10-12m and a top backfill height of 4-6m.

[0019] Figure 1-7 As shown, the construction steps for the roof support structure of the subsequent backfilling of the stope during this vertical deep-hole stage ore cutting are as follows: 1) The ore blocks are arranged along the strike of the ore body, and the ore body is divided into several continuous ore rooms, which are successively divided into primary ore rooms and secondary ore rooms; 2) The ore block is divided into several stages along the vertical direction. Drilling chamber pillars 3 are designed and arranged at the top of each stage, and then drilling chambers 4 are arranged. 3) Above the rock drilling chamber 4, below the location of the material outlet of the filling borehole 6, design and form an irregular top plate 5.

[0020] Figure 1-7 As shown, the mining method of this vertical deep hole stage ore-cutting and subsequent backfilling stope adopts the above-mentioned top structure and includes the following steps: 1) In the first-step and second-step mining stages of the ore block, drill upward medium-deep blast holes from the bottom trench roadway 1 and drill downward deep blast holes from the rock-cutting chamber 4 to blast the perforated blasting area I, which collapses to form ore pile II, and ore is extracted through the ore extraction roadway 2. 2) The first-step mining stope is mined indirectly, with one stope mined at a time, meaning that after mining the first-step mining stope, there is a two-stop interval before mining the next first-step mining stope in the next direction; after the ore body of the first-step mining stope is extracted, the goaf is cemented and backfilled; the second-step mining stope is mined by first mining one side of the cemented and backfilled stope, then mining the other side of the cemented and backfilled stope, with one stope mined every three days, meaning that after mining the second-step mining stope, there is a one-stop interval between the first-step mining stope + the second-step mining stope + the first-step mining stope in the next direction before mining the next second-step mining stope; after the ore body of the second-step mining stope is extracted, the goaf is non-cemented and backfilled; such as Figure 1 As shown in the stope void area III and stope filling area IV; 3) In the previous stage of the bottom trench roadway 1, fill borehole 6 and exhaust borehole 7 are constructed every 20 to 30 m. Fill borehole 6 and exhaust borehole 7 are set at intervals. The diameter of fill borehole 6 is 150 to 300 mm, and the diameter of exhaust borehole 7 is 50 to 150 mm.

[0021] Example: The following specific steps are used in the vertical deep hole stage ore cutting and subsequent backfilling mining top connection method.

[0022] Figures 1-7As shown, the ore blocks are arranged perpendicular to the strike of the ore body. The ore body width L is 120m, and it is divided into a first-stage mining room and a second-stage mining room. The width of the first-stage mining room L1 is 20-25m, the width of the second-stage mining room L2 is 20-25m, the stage height H is 60-120m, and the height of the top pillar h is 10-20m.

[0023] Each stage of the stope is designed with drilling chamber top pillar 3 and drilling chamber 4. After the ore body collapses, it converges in the bottom trench roadway 1 and is transported away through the bottom ore extraction roadway 2. The drilling roadway in the previous stage is designed according to the location of the material discharge hole in the roof filling borehole and the size of the irregular roof. The material discharge borehole is located on the intersection line between the roof boundary and the boundary of the adjacent two-stage ore body, 2.5m above the roof boundary.

[0024] The irregular roof slab 5 is designed with a width of 4m for the upper platform, that is, the distance between the edge of the upper platform 51 and the boundary of the adjacent two-step mining body is 4m, and the height of the step formed is 2m. The lower platform 53 extends to the boundary of the stope with a slope of 3 to 4° in the direction of the forward direction.

[0025] After the ore blasting and extraction in the stope are completed, the goaf is backfilled. Backfilling borehole 6 and venting borehole 7 are constructed within the previous stage's bottom trench roadway, spaced 30m apart. The diameter of both backfilling borehole 6 and venting borehole 7 is 150mm. After the cemented backfilling and roof connection of the first-stage stope is completed... Figure 4 As shown. The same procedures were used for excavation and backfilling of the two-stage mining stope. The two-stage mining stope used non-cemented backfilling, as shown... Figure 6 As shown.

[0026] When filling using this method, the filling and roof connection rate can reach 90-95%, ensuring the quality of the roof connection. The process is simple, easy to construct, and low in cost.

Claims

1. A structure for roof support in a vertical deep-hole stage ore-cutting and subsequent backfilling stope, characterized in that: The ore blocks are arranged along the strike of the ore body, and the ore body is divided into several continuous mining houses, which are divided into first-stage mining houses and second-stage mining houses in sequence. The ore blocks are divided into several stages along the vertical direction, and each stage is equipped with a drilling chamber (4) and a bottom-cutting channel (1). The bottom-cutting channel (1) of the previous stage has a filling borehole (6) drilled into the drilling chamber (4) of the adjacent mining house of the next stage. A special-shaped roof plate (5) is designed above the drilling chamber (4). The special-shaped roof plate (5) is stepped, with the upper platform located on one side of the material outlet of the filling borehole (6) and the lower platform diagonally spreading downward to the other side of the drilling chamber (4).

2. The structure for subsequent backfilling of a vertical deep-hole stage ore-cutting stope according to claim 1, characterized in that: The slope of the platform under the irregular top plate (5) is 3-4°.

3. The structure for subsequent backfilling of a vertical deep-hole stage ore-cutting stope according to claim 1, characterized in that: The width of the upper platform in the irregular top plate (5) is 3 to 5 m.

4. A vertical deep-hole stage ore-filling subsequent backfilling stope roof structure according to claim 1, 2 or 3, characterized in that: The step height of the irregular top plate (5) is 1.5 to 2m.

5. A method for mining a vertical deep-hole stage ore-cutting followed by backfilling in a stope, employing the roof support structure described in claim 1, 2, or 3, characterized in that, The steps include: 1) Drilling upward medium-deep blast holes from the bottom trench tunnel (1), and drilling downward deep blast holes from the rock chamber (4) to carry out blasting and ore extraction. 2) Indirect mining is used for one-step mining; for two-step mining, one side of the cemented ore chamber is mined first, and then the other side of the cemented ore chamber is mined. 3) After the ore body of the first-stage mining stop is extracted, the goaf is cemented and backfilled; after the ore body of the second-stage mining stop is extracted, the goaf is non-cemented and backfilled. 4) Construction of filling boreholes (6) in the bottom trench tunnel (1) of the previous stage.

6. A method for mining a vertical deep-hole stage ore extraction followed by backfilling in a stope, as described in claim 5, characterized in that: In step 4), the spacing of the filling boreholes (6) is 40-60m.

7. A method for mining a vertical deep-hole stage ore extraction followed by backfilling in a stope, as described in claim 5 or 6, characterized in that: In step 4), an exhaust hole (7) is also constructed, and the filling hole (6) and the exhaust hole (7) are set at intervals.

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