Bottom structure for high-efficient mining of unstable ore body by stage method and construction method thereof

Abstract

The bottom structure and its construction method for efficient ore extraction using the staged method in unstable ore bodies: First, the ore body is divided into panels. Then, each panel is further divided into stopes and inter-panel pillars, with the stopes numbered sequentially as ①②③④⑤… Finally, a cross-cutting roadway is arranged in the middle of the bottom of the inter-panel pillars. A trench roadway is arranged in the middle of the bottom of stope ③. Ore extraction roadways connecting the cross-cutting roadways on both sides are arranged in the middle of the bottom of stopses ① and ⑤. Between the trench roadways and the ore extraction roadways… The ore loading path is vertically and evenly distributed, with upward fan-shaped holes constructed in the trench roadway. After blasting, the remaining triangular ore and the ore body between the bottom roadway form a base pillar. The collapsed ore is loaded and transported out by a loader in the trench roadway. The construction method is based on the structural parameters of the stage open stope and the mining technology conditions of the ore body. It has six steps and has the advantages of structural capacity that can meet the operation of a 14t loader and achieve an ore output capacity of more than 2000t / d. The construction steps are simple and safe.

Description

Technical Field

[0001] This invention relates to the field of underground mining technology, and in particular to a bottom structure and its construction method for efficient ore extraction in the staged method for unstable ore bodies. Background Technology

[0002] The bottom ore extraction structure in staged stopes is a crucial technical aspect of underground mining. The bottom structure largely determines the stope's production capacity, the amount of preparatory work, labor productivity, and safety. The bottom structure must ensure sufficient stability throughout the ore extraction process, while its parameters guarantee adequate space for shoveling, loading, and transporting ore, as well as sufficient flexibility and maneuverability for the loader.

[0003] Unstable ore bodies are generally unsuitable for staged mining. In recent years, mining scientists, aiming to improve mining efficiency and reduce production costs, have restructured the mining environment by implementing scientifically sound support methods for the stope roof and sidewalls, and by employing blasting control during the mining process. This has enabled the application of staged mining in unstable ore bodies. When applying staged mining to unstable ore bodies, to further ensure safety during the mining process, a strong mining and filling operation mode is required to shorten the entire mining flow, necessitating the use of large-scale ore extraction equipment. Because the structural parameters of staged stopes are smaller than those of stable ore bodies, and the stability of the ore body is also less stable, conventional diamond-shaped bottom extraction structures and symmetrical oblique bottom extraction structures cannot meet the requirements for safe and efficient ore extraction.

[0004] To address the aforementioned issues, several methods have been proposed: CN202511623080.0, "Mining Method for Extremely Thick Ore Bodies Based on Combined Stope Bottom Structure," employs a combination of Y-shaped high trenches and wedge-shaped rock pillars, with a bucket shaft and high funnel receiving system set up in the footwall. Ore is guided into the loading path via longitudinal trenches. However, this invention relies heavily on the rock pillars for support, is highly susceptible to the dip angle of the ore body, and the combination of bucket shafts and trenches is complex to construct and has limited functionality. Furthermore, the receiving system needs to be reconstructed during the second-stage mining phase, resulting in poor process flexibility, limited loading space, and difficulty in adapting to the efficient operation of large loaders; CN202511623078.3, "Based on Longitudinal and Transverse Bidirectional Layout..." The invention, titled "Mining Method for Extremely Thick Ore Bodies with Fixed Bottom Structures," is designed for extremely thick ore bodies with an upright hanging wall and an inclined footwall. It divides the block into a stage stop on the hanging wall side and a segmented stop on the footwall side, arranging two sets of bottom structures, one horizontal and one vertical. After segmented mining and backfilling from the hanging wall to the footwall, the stage stop is then mined along the strike. However, the bottom structure arrangement of this invention is complex, requiring the simultaneous construction of two sets of ore receiving systems, resulting in a large amount of mining and cutting work. It necessitates auxiliary works such as inclined shafts and ore passes to connect the two systems, leading to cumbersome construction organization, poor process flexibility, and the dispersed arrangement of the two bottom structures, which is not conducive to the centralized and efficient extraction of ore by large loaders. Furthermore, it is difficult to apply under unstable ore body conditions.

[0005] Therefore, it is of great significance to develop a bottom structure and its construction method for efficient ore extraction in the stage method for unstable ore bodies. Summary of the Invention

[0006] The objective of this invention is to overcome the shortcomings of existing technologies. Addressing the mining conditions and ore extraction requirements of unstable ore bodies, and combining this with staged mining techniques, a bottom structure and its construction method for efficient staged ore extraction from unstable ore bodies are proposed. The aim is to solve the following two problems:

[0007] (1) The commonly used bottom structure trench roadways, ore extraction roadways and ore loading access roads have an angle of 45 to 60 degrees. The angle is easy to crack, break or even collapse. This will be more prominent in unstable ore bodies, which will affect safe mining and ore extraction efficiency.

[0008] (2) When using the stage method for unstable ore bodies, the stope structure parameters are relatively small, while the high-intensity ore extraction requirements require large equipment with larger cross sections and longer loading routes. The commonly used bottom structure cannot meet the high-efficiency operation of the loader.

[0009] This invention proposes a bottom structure for efficient ore extraction in unstable ore bodies using a staged method. It involves vertically arranging the loading access roadway and the trench roadway, forming an intersecting network to create an I-shaped stress transfer framework. At the intersection areas, a bidirectional stress arch convergence zone is formed, achieving multi-level decomposition and synergistic load-bearing of the stress field, thus solving the safety and stability issues of the bottom structure. In conjunction with the "three-out-of-one" mining method, the trench roadway and ore extraction roadway are located at the center of adjacent stopes, with the loading access roadway interspersed across stopes on both sides of the trench roadway, forming sufficient loading length. This structure can accommodate a 14t loader and achieve an ore extraction capacity of over 2000t / d.

[0010] The objective of this invention is achieved through the following technical solution:

[0011] The bottom structure for efficient ore extraction in the stage method for unstable ore bodies first divides the ore body into panels, then divides the panels into stopes and inter-panel pillars, and numbers the stopes sequentially as ①②③④⑤… Finally, a cross-vein roadway is arranged in the middle of the bottom of the inter-panel pillar, a trench roadway is arranged in the middle of the bottom of stope ③, and an ore extraction roadway connecting the cross-vein roadways on both sides is arranged in the middle of the bottom of stopes ① and ⑤. Ore loading paths are evenly distributed vertically and interspersed between the trench roadway and the ore extraction roadway. Upward fan-shaped holes are constructed in the trench roadway. After blasting, the remaining triangular ore and the ore body between the bottom roadway form the bottom pillar. The collapsed ore is loaded and transported out by a loader in the trench roadway.

[0012] The construction method for the bottom structure used in the staged method for efficient ore extraction in unstable ore bodies, based on the stope structure parameters and mining technology conditions of the ore body, includes the following specific steps:

[0013] Step 1: Divide the ore body into panels, then divide each panel into stopes and inter-panel pillars, and number the stopes sequentially in the order ①②③④⑤...;

[0014] Step 2: Arrange the cross-cut roadway in the middle of the bottom of the column in the panel section. At the middle of the bottom of the ③ mining area, construct the trench roadway vertically from the cross-cut roadway to the cross-cut roadway on the other side.

[0015] Step 3: At the middle position of the bottom of mining areas ① and ⑤, construct the ore extraction roadway vertically from the cross-vein roadway to the cross-vein roadway on the other side;

[0016] Step 4: Construct a loading roadway from the middle of the trench roadway to the ore extraction roadway of mining area ①, and connect it with the ore extraction roadway; construct loading roads from ¼ and ¾ of the trench roadway to the ore extraction roadway of mining area ⑤, and connect them with the ore extraction roadway.

[0017] Step 5: Construct upward fan-shaped holes in the trench tunnel. The remaining triangular ore after blasting and the ore body between the bottom tunnel form a bottom pillar. The collapsed ore is loaded and transported out by a loader in the loading roadway within the trench tunnel.

[0018] Compared with the prior art, the innovative points, advantages, and effects of this invention are as follows:

[0019] (1) Safer bottom structure: Since the trench roadway, ore extraction roadway and ore loading roadway are arranged vertically, the stress at the roadway intersection is more uniform and it is easier to achieve stress balance. This avoids the current common bottom structure from cracking, breaking or even collapsing due to the 45-60° angle, which affects safe mining and ore extraction efficiency.

[0020] (2) Higher ore extraction efficiency of the bottom structure: Since large loaders can be used for ore extraction, the ore extraction efficiency is improved, the entire mining process time is shortened, and the stability of the mining process is facilitated. For example, in a mining area with a width of 12m, the distance between the conventional bottom structure trench roadway and the ore extraction roadway is 7.8m. The ore loading roadway is arranged at a minimum angle of 45°, and its length is about 11m. The net length of the LH514 type loader is 10.87m, and the minimum net length of the ore loading roadway is required to be 13.67m. The conventional bottom structure is too short and cannot fully utilize the efficiency of the loader. The distance between the ore extraction roadway and the trench roadway of this invention is 19.8m, and the effective length of the ore extraction roadway is about 15m, which can meet the loader's loading distance requirements and achieve efficient loading operations.

[0021] (3) The bottom pillar is easier to recover: Since the bottom structure is arranged vertically, the bottom pillar, filling body and ore body are distributed in a more regular and regular manner, making it easier to recover the bottom pillar ore body and obtain a higher recovery rate. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the construction process of a bottom structure for efficient ore extraction in an unstable ore body stage method, based on the present invention.

[0023] Figure 2 This is a schematic diagram of the bottom structure for efficient ore extraction using a staged method for unstable ore bodies, as proposed in this invention.

[0024] Figure 3 for Figure 2 The diagram shows a frontal view of the bottom structure used for efficient ore extraction in the staged method for unstable ore bodies.

[0025] Figure 4 for Figure 2 The diagram shows a side view of the bottom structure used for efficient ore extraction in the stage method for unstable ore bodies.

[0026] The symbols in the attached diagram represent:

[0027] 1. Stope 2. Panel section pillar 3. Numbering 4. Crosscut roadway 5. Trench roadway 6. Ore extraction roadway 7. Loading access roadway 8. Bottom pillar 9. Collapsed ore 10. Upward fan-shaped hole

[0028] The present invention will now be described in further detail with reference to the accompanying drawings. Detailed Implementation

[0029] As attached Figures 2-4 As shown, the bottom structure for efficient ore extraction in the stage method for unstable ore bodies first divides the ore body into panels, then divides the panels into stopes 1 and inter-panel pillars 2, and numbers the stopes 1 sequentially as ①②③④⑤… Finally, a cross-vein roadway 4 is arranged in the middle of the bottom of the inter-panel pillar 2, a trench roadway 5 is arranged in the middle of the bottom of stope ③, and an ore extraction roadway 6 connecting the cross-vein roadways 4 on both sides is arranged in the middle of the bottom of stopses ① and ⑤. Ore loading paths 7 are evenly distributed vertically and interspersed between the trench roadway 5 and the ore extraction roadway 6. An upward fan-shaped hole 10 is constructed in the trench roadway 5. The remaining triangular ore after blasting and the ore body between the bottom roadway form the bottom pillar 8. The collapsed ore 9 is in the trench roadway 5, and the loader loads and transports it out in the ore loading path 7.

[0030] The bottom structure of the present invention may further be:

[0031] The loading roadway 7 is arranged perpendicularly to the trench roadway 5 and the ore outlet roadway 6. No sharp corners are formed at the intersection of the roadways. A two-way stress arch convergence zone is formed in the intersection area, which improves the safety and stability of the bottom structure.

[0032] The loading access road 7 is arranged perpendicularly to the trench roadway 5 and the ore extraction roadway 6. When the first-stage mining area is finished and the second-stage mining area is mined, the functions of the trench roadway 5 and the ore extraction roadway 6 are interchanged. The loading access road 7 and their relative positions remain unchanged, so efficient ore extraction can still be achieved and less ore residue is generated.

[0033] The trench roadway 5, the ore extraction roadway 6, and the ore loading access roadway 7 are arranged regularly and squarely in the bottom pillar 8. After the mining is completed, it becomes simpler to recover the bottom pillar 8 and a higher recovery rate can be obtained.

[0034] The trench roadway 5 and the ore extraction roadway 6 are arranged in two adjacent mining areas. The large distance between the roadways allows the loading access roadway 7 to have sufficient length to allow large loaders to complete the loading, thereby improving ore extraction efficiency, shortening the mining process time, and contributing to the stability of the mining area recovery process.

[0035] As attached Figure 1 As shown, the construction method for the bottom structure used in the staged method for efficient ore extraction in unstable ore bodies, based on the stope structure parameters of the staged open stope subsequent backfilling method and the mining technology conditions of the ore body, includes the following specific steps:

[0036] Step 1: Divide the ore body into panels, then divide each panel into stope 1 and panel pillar 2, and number each stope 1 sequentially as follows: ①②③④⑤...;

[0037] Step 2: Arrange the cross-vein roadway 4 in the middle of the bottom of the column 2 in the panel section. At the middle of the bottom of the ③ mining area, construct the trench roadway 5 vertically from the cross-vein roadway 4 to the cross-vein roadway 4 on the other side.

[0038] Step 3: At the middle position of the bottom of mining areas ① and ⑤, construct the ore extraction roadway 6 vertically from the cross-vein roadway 4 to the cross-vein roadway 4 on the other side;

[0039] Step 4: Construct loading access road 7 from the middle of trench roadway 5 towards ore extraction roadway 6 in mining area ①, and connect it to ore extraction roadway 6; construct loading access roadway 7 from ¼ and ¾ of trench roadway 5 towards ore extraction roadway 6 in mining area ⑤, and connect it to ore extraction roadway 6.

[0040] Step 5: Construct an upward fan-shaped hole 10 in the trench roadway 5. The remaining triangular ore after blasting and the ore body between the bottom roadway form a bottom pillar 8. The collapsed ore 9 is in the trench roadway 5. The loader loads and transports it out in the ore loading roadway 7.

[0041] As described above, the present invention can be well implemented. The above embodiments are only the best implementations of the present invention, but the implementation of the present invention is not limited to the above embodiments. Other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are all included within the protection scope of the present invention.

Claims

1. A bottom structure for efficient ore extraction in a staged method for unstable ore bodies, characterized in that... First, the ore body is divided into panels, then the panels are divided into stopes (1) and inter-panel pillars (2), and the stopes (1) are numbered sequentially (3) as ①②③④⑤……. Finally, a cross-vein roadway (4) is arranged in the middle of the bottom of the inter-panel pillar (2), a trench roadway (5) is arranged in the middle of the bottom of stope ③, and an ore extraction roadway (6) connecting the cross-vein roadways (4) on both sides is arranged in the middle of the bottom of stopes ① and ⑤. Ore loading roads (7) are evenly distributed vertically between the trench roadway (5) and the ore extraction roadway (6). An upward fan-shaped hole (10) is constructed in the trench roadway (5). The remaining triangular ore after blasting and the ore body between the bottom roadway form a bottom pillar (8). The collapsed ore (9) is in the trench roadway (5), and the shovel is loaded and transported out in the ore loading roadway (7).

2. The bottom structure according to claim 1, characterized in that: The loading roadway (7) is arranged perpendicularly to the trench roadway (5) and the ore outlet roadway (6). No sharp corners are formed at the intersection of the roadways. A two-way stress arch convergence area is formed in the intersection area, which improves the safety and stability of the bottom structure.

3. The bottom structure according to claim 1 or 2, characterized in that: The loading roadway (7) is arranged perpendicularly to the trench roadway (5) and the ore extraction roadway (6). When the first-stage mining area is finished and the second-stage mining area is mined, the functions of the trench roadway (5) and the ore extraction roadway (6) are interchanged. The loading roadway (7) and their relative positions remain unchanged, so efficient ore extraction can still be achieved and a small amount of ore residue is generated.

4. The bottom structure according to claim 1, characterized in that: The trench roadway (5), the ore extraction roadway (6) and the ore loading roadway (7) are arranged regularly and squarely in the bottom pillar (8). After the mining is completed, it becomes simpler to recover the bottom pillar (8) and a higher recovery rate can be obtained.

5. The bottom structure according to claim 1 or 4, characterized in that: The trench roadway (5) and the ore extraction roadway (6) are arranged in two adjacent mining areas. The distance between the roadways is relatively large, which allows the loading roadway (7) to have sufficient length to allow large loaders to complete the loading, improve the ore extraction efficiency, shorten the mining process time, and help stabilize the mining process.

6. A construction method for the bottom structure used in the staged extraction method for unstable ore bodies with high efficiency, characterized in that... Based on the stope structure parameters and mining technology conditions of the ore body using the staged open stope subsequent filling method, the specific steps are as follows: Step 1: Divide the ore body into panels, then divide each panel into stopes (1) and inter-panel pillars (2), and number each stope (1) sequentially (3) in the order of ①②③④⑤...; Step 2: Arrange the cross-vein roadway (4) in the middle of the bottom of the column (2) in the panel section. At the middle position of the bottom of the ③ mining area, construct the trench roadway (5) vertically from the cross-vein roadway (4) to the cross-vein roadway (4) on the other side. Step 3: At the middle position of the bottom of the ① and ⑤ mining areas, construct the ore extraction roadway (6) vertically from the cross-vein roadway (4) to the cross-vein roadway (4) on the other side. Step 4: Construct the loading roadway (7) from the middle position of the trench roadway (5) to the ore extraction roadway (6) of the ① mining area, and connect it with the ore extraction roadway (6); Construct the loading roadway (7) from ¼ and ¾ of the trench roadway (5) to the ore extraction roadway (6) of the ⑤ mining area, and connect it with the ore extraction roadway (6); Step 5: Construct an upward fan-shaped hole (10) in the trench roadway (5). The remaining triangular ore after blasting and the ore body between the bottom roadway form a bottom pillar (8). The collapsed ore (9) is in the trench roadway (5). The loader loads and transports it out in the ore loading roadway (7).

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