Cross-section of the stope structure and its recovery process

Abstract

The stope structure of cross section and its recovery process include web, column limb, cutting shaft, rectangular strip column, L-shaped strip column, ore drawing connecting roadway and deep hole; single cross section is composed of four column limbs and middle web, the cross section of column limb and web is square; no column is left between adjacent stope, cross section is densely laid with each other, its recovery process includes completion of stope cutting engineering construction; cutting shaft constructed in the center of web is expanded as free surface; after expansion, perforation blasting of web is completed, the empty area after web collapse is free surface, four column limbs are blasted and side collapse at the same time; the collapsed ore is shovelled out of stope through bottom ore drawing connecting roadway, after the ore is drawn out, the goaf is filled, the side slope and roof of the stope with rectangular cross section structure have good stability, the side slope and roof are not easy to collapse, the risk of stope personnel and equipment operation is low, safety and high efficiency are achieved.

Description

Technical Field

[0001] This invention relates to the field of mining technology, specifically to a cross-shaped cross-section stope structure and its mining process. Background Technology

[0002] Currently, in both domestic and international metal and non-metal mines using segmented or staged mining methods, the stope cross-section typically employs a conventional rectangular structure. Considering the stability of the stope's sidewalls and roof, the stope width and length cannot be too wide or too long; otherwise, there is a risk of sidewall and roof collapse. Developing a large-scale stope structure with optimal parameters to ensure safe, efficient, and low-cost mining of thick or extremely thick ore bodies remains a global industry challenge.

[0003] To address the aforementioned issues, several patents have been published, including CN110878695A, "A method for arranging stope structures suitable for continuous multi-step mining." This technology uses a concave hexagonal cross-section with a smaller middle and larger ends for the first-step stope in segmented or staged mining, and an outwardly convex hexagonal cross-section with a larger middle and smaller ends for the second-step stope. However, this technology does not consider the excessively large exposed area of ​​the stope sidewalls and roof, thus failing to truly achieve stability for the stope sidewalls and roof. Furthermore, the stope cross-section disclosed in CN110878695A is rectangular, which also exhibits the shortcomings of the CN110878695A patent.

[0004] In summary, existing technologies cannot achieve both structural stability of the sidewalls and roof of the mining area and good mining safety.

[0005] Therefore, it is of great significance to develop a cross-shaped mining structure and its mining technology. Summary of the Invention

[0006] The objective of this invention is to overcome the shortcomings of the prior art and provide a cross-shaped cross-section stope structure and its mining process. This invention can solve the problems of poor stability of the sidewalls and roof of rectangular cross-section stopes, and the easy collapse of the sidewalls and roof. It can also reduce the risks of personnel and equipment operation in the stope, and achieve safe and efficient mining.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] The cross-shaped cross-section of the stope structure includes a web, columns, cutting risers, rectangular columns, L-shaped columns, ore-exit connecting roadways, and deep holes. A single cross-shaped cross-section is composed of four columns and a central web, and both the columns and the web have square cross-sections. No inter-column columns are left between adjacent stops, and they are closely interwoven through cross-shaped cross-sections.

[0009] The specific process steps and conditions for the mining technology used in cross-shaped stopes are as follows:

[0010] Complete the mining and cutting engineering construction of the mining area; widen the trench using the cutting riser constructed at the center of the web as the free face; after widening the trench, complete the perforation blasting of the web; simultaneously blast the four pillars side-breaching using the void area after the web caving as the free face; the caving ore is shoveled out of the mining area through the bottom ore-exit connecting roadway, and the goaf is filled after the ore is completely removed.

[0011] The innovative aspects of this invention:

[0012] (1) The structural form breaks the limitations of traditional mining site design, abandons the inherent design thinking of traditional single rectangular mining site cross section in the mining field, and innovatively introduces cross-shaped cross section mining site structure, subverting the conventional regular and independent mining site cross section form mode, and providing a brand-new design idea and form scheme for mining site structure optimization.

[0013] (2) Innovative spatial layout to achieve close-knit complementary interlocking of mining areas. The first cross-shaped cross section close-knit layout method is created. By utilizing the morphological advantages of the cross-shaped structure, adjacent mining areas can achieve spatial complementarity and interlocking, which solves the pain points of traditional rectangular mining areas being independently arranged, lacking spatial linkage and poor connectivity, and constructs an overall interconnected mining area spatial system.

[0014] (3) The process is innovative and compatible with mainstream mining methods. The cross-shaped dense cross section structure is innovatively adapted to the two mainstream downhole mining processes of segmented method and staged method. This breaks through the problem of insufficient compatibility between the new cross section structure and traditional mining process. There is no need to significantly modify the existing mining process. The technology is more practical and versatile.

[0015] (4) Performance innovation significantly improves the stability of the mining area structure. Relying on the overall structural advantages of the interlocking and complementary space of the cross-shaped mining area, it changes the defects of the rectangular mining area's single structure and weak stability, effectively strengthens the integrity and stability of the traditional structure of the overall mining area, and can significantly improve the safety factor of underground mining.

[0016] Compared with the prior art, the advantages or effects of the present invention are as follows:

[0017] (1) Improved structural stability: Hydraulic static fracturing only applies micro-disturbance to the backfill around the stope, avoiding the destruction of the backfill caused by direct blasting, thereby significantly enhancing the overall structural stability of the stope;

[0018] (2) Simplified construction process: By dividing the area into holes and arranging them in a combined manner, the pre-installation process of the complex support structure of flexible mesh or reinforced beam is eliminated, which reduces the difficulty and cost of construction.

[0019] (3) Effective control of dilution rate: Deep hole blasting is concentrated on the ore and rock in the middle area of ​​the stope, and the auxiliary holes drive the ore and rock in the fracturing area to fall into the ore. The arrangement of fracturing holes around the perimeter reduces the amount of filling material mixed into the ore pile, directly solving the problem of ore dilution caused by the destruction of filling material.

[0020] (4) Applicability and efficiency are both taken into account: This method is applicable to ore bodies with different occurrence characteristics in the end or middle cutting groove, and by combining static fracturing and blasting, it takes into account both ore extraction efficiency and safety. Attached Figure Description

[0021] Figure 1 This is a schematic plan view of a cross-shaped mining structure proposed in this invention, in which the structures are closely connected to each other.

[0022] Figure 2 for Figure 1 The diagram shows the structural unit composition of the cross-section mining area.

[0023] Figure 3 for Figure 1 The diagram shows a frontal view of a cross-section mining area.

[0024] Figure 4 for Figure 1 The diagram shows a cross-sectional view of the top cutting project in the cross-section of the mining area.

[0025] Figure 5 for Figure 1 The diagram shows a cross-sectional view of the ore extraction structure at the bottom of the cross-section of the mining area.

[0026] Figure 6 This is a schematic diagram of the construction process for a cross-shaped mining structure.

[0027] The symbols in the attached diagram represent:

[0028] A. Web B. Column 1. Cutting riser 2. Rectangular column 3. L-shaped column 4. Mine access roadway 5. Deep hole

[0029] The present invention will now be described in further detail with reference to the accompanying drawings. Detailed Implementation

[0030] like Figures 1-5 As shown, the cross-shaped cross-section of the stope structure includes a web A, pillars B, cutting riser 1, rectangular pillars 2, L-shaped pillars 3, ore connection roadway 4, and deep hole 5. A single cross-shaped cross-section is composed of four pillars B and the middle web A, and both the pillars B and the web A have square cross-sections. No inter-pillars are left between adjacent stops, and they are closely connected by cross-shaped cross-sections.

[0031] The mining structure of the present invention can be further described as follows:

[0032] The cross-shaped cross-section of the mining sidewall is composed of 12 small sidewalls of the same area.

[0033] A cutting well 1 is arranged at the center of the cross-shaped cross section.

[0034] The top layer of the four column members B of the cross-shaped cross section shall have 2 to 3 rectangular strip columns 2 with a width of 2 to 4 m.

[0035] At the four corners of the top cut of the cross-shaped cross section of the middle web A, an L-shaped column 3 with a width of 2-4m is left.

[0036] Each of the cross-shaped mining areas is equipped with a conventional ore receiving funnel.

[0037] The four ore-exit connecting tunnels 4 with the cross-shaped cross section are connected to the bottom of the ore-receiving funnel.

[0038] like Figure 6 As shown, the specific process steps and conditions for the mining technology of the cross-shaped section stope are as follows:

[0039] S1. Complete the mining and cutting engineering construction in the mining area;

[0040] S2. Expand the trench using the cutting well 1 constructed at the center of web A as the free surface;

[0041] S3. After widening the groove, complete the perforation and blasting of the web A;

[0042] S4. Using the void area after the collapse of the web A as the free surface, simultaneously perform blasting and side collapse on the four column legs B.

[0043] S5. The collapsed ore is shoveled out of the mining area through the bottom ore-exit connecting roadway 4. After the ore is completely removed, the goaf is filled.

[0044] The process of the present invention can be further described as follows:

[0045] In step S4, the four column members B simultaneously perform deep hole 5 side chipping, which is completed in multiple stages.

[0046] In step S4, the blasting distance of the four columns B remains consistent each time, resulting in the best compression blasting effect.

[0047] Example

[0048] A mining company's copper-producing metal mine plans to mine an ore body at an elevation of -200m to -150m, with a thickness of 20-120m and a dip angle of 80-90°, constituting a steeply dipping, extremely thick, and large ore body. The challenge lies in addressing the existing problems of poor roof and sidewall stability, high collapse risk, and low ore extraction efficiency in large-diameter deep-hole staged open-cut stopes. By utilizing a cruciform stope cross-section, the stability of the structural group is ensured through close-packing. Furthermore, the sidewalls of the cruciform stope consist of 12 mutually perpendicular smaller sidewalls, and the roof cross-section is also cruciform. This structure is more conducive to the stability of the sidewalls and roof within a single stope, and the cruciform stope cross-section structure can achieve greater production capacity, pioneering the application of cruciform stope cross-sections in staged stopes.

[0049] The above embodiments are only the best implementations of the present invention, but the implementations of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A cross-shaped mining structure, characterized in that... It includes a web (A), columns (B), cutting risers (1), rectangular columns (2), L-shaped columns (3), ore-exit connecting roadways (4), and deep holes (5); a single cross-shaped cross section is composed of four columns (B) and the middle web (A), and the cross sections of the columns (B) and the web (A) are both square; no inter-column is left between adjacent mining areas, and they are closely laid together by cross-shaped cross sections.

2. The mining area structure according to claim 1, characterized in that: The cross-shaped column (B) and web (A) have square cross-sections with side lengths of 10-20m.

3. The mining area structure according to claim 1, characterized in that: The cross-shaped cross-section of the mining sidewall is composed of 12 small sidewalls of the same area.

4. The mining area structure according to claim 1, characterized in that: A cutting ceiling (1) is arranged at the center of the cross-shaped cross section.

5. The mining area structure according to claim 1, characterized in that: The top cut of the four columnar members (B) of the cross-shaped cross section shall have 2 to 3 rectangular strip columns (2) with a width of 2 to 4 m.

6. The mining area structure according to claim 1, characterized in that: At the four corners of the cut-off top layer of the cross-shaped cross section of the middle web (A), an L-shaped column (3) with a width of 2~4m is left.

7. The mining area structure according to claim 1, characterized in that: Each of the cross-shaped mining areas is equipped with a conventional ore receiving funnel.

8. The mining area structure according to claim 1, 2, 3, 4, 5, 6, or 7, characterized in that: The four ore-exit connecting tunnels (4) of the cross-shaped cross section are connected to the bottom of the ore-receiving funnel.

9. A mining process for a cross-shaped stope structure, characterized in that... The specific process steps and conditions are as follows: S1. Complete the mining and cutting engineering construction in the mining area; S2. The groove is widened using the cutting well (1) constructed at the center of the web (A) as the free surface; S3. After widening the groove, complete the perforation blasting of the web (A); S4. Using the void area after the caving of the web (A) as the free surface, simultaneously perform blasting and side caving on the four pillars (B); S5. The collapsed ore is shoveled out of the mining area through the bottom ore-exit connecting roadway (4), and the goaf is filled after the ore is completely removed.

10. The mining process according to claim 9, characterized in that: In step S4, the four columns (B) simultaneously perform deep hole (5) side breakage, which is completed in multiple stages.

11. The mining process according to claim 9 or 10, characterized in that: In step S4, the blasting distance of the four columns (B) remains consistent for each blast, resulting in the best compression blasting effect.

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