Filling structure of open pit and filling method of open pit

Abstract

The application provides a filling structure of an open pit and a filling method of the open pit. The filling structure of the open pit comprises: an isolation layer arranged at the bottom of the open pit, the isolation layer being filled with a first slurry; a first filling area arranged above the isolation layer and adjacent to a broken rock mass slope, the first filling area being filled with multiple layers of a second slurry, the strength of the first slurry being greater than that of the second slurry; a second filling area arranged above the isolation layer, the second filling area comprising an area in the open pit except the first filling area, the second filling area being filled with multiple layers of a third slurry, the strength of the second slurry being greater than that of the third slurry; a repair layer arranged above the first filling area and the second filling area; and a vegetation layer planted on the repair layer. The technical scheme of the application can effectively solve the problem that the open pit in the related art is prone to causing geological disasters and threatening underground production.

Description

Technical Field

[0001] This invention relates to the field of open-pit filling, and more specifically, to a filling structure and a filling method for open-pit pits. Background Technology

[0002] Many metal mines employ both open-pit and underground mining methods, with open-pit mines forming after the completion of open-pit mining.

[0003] The aforementioned open-pit mines have, on the one hand, damaged the surface ecological environment, resulting in the complete loss of vegetation communities, and on the other hand, made the mine slopes prone to geological disasters such as landslides and mudslides. During the rainy season, open-pit mines are also prone to surface runoff flowing into the mines, causing water damage and threatening underground production. Summary of the Invention

[0004] The main objective of this invention is to provide a filling structure and a filling method for open-pit mines, in order to solve the problem that open-pit mines in related technologies are prone to causing geological disasters and threatening underground production.

[0005] To achieve the above objectives, according to one aspect of the present invention, a filling structure for an open pit is provided, comprising: an isolation layer disposed at the bottom of the open pit, the isolation layer being filled with a first slurry; a first filling region disposed above the isolation layer and adjacent to a fractured rock slope, the first filling region being filled with multiple layers of a second slurry, the strength of the first slurry being greater than the strength of the second slurry; a second filling region disposed above the isolation layer, the second filling region including the area within the open pit excluding the first filling region, the second filling region being filled with multiple layers of a third slurry, the strength of the second slurry being greater than the strength of the third slurry; a repair layer disposed above the first and second filling regions; and a vegetation layer planted on the repair layer.

[0006] By applying the technical solution of this invention, a high-strength first slurry is used to fill the bottom of the open pit to form an isolation layer. This isolation layer covers the bottom of the open pit, sealing the hydraulic channels between the open pit and the underground mining system, preventing rainwater and other water from seeping into the ground and threatening underground production. A first filling area and a second filling area are set above the isolation layer to fill the open pit. Specifically, the first filling area is located close to the slope of the fractured rock mass, while the second filling area is located away from the slope. The first filling area is filled with a higher-strength second slurry, resulting in higher strength after filling, while the second filling area has relatively lower strength. This approach reduces costs while ensuring the overall strength of the filling structure. Filling the open pit entirely would be difficult; in this application, the first and second filling areas are filled in layers, effectively reducing construction difficulty. Furthermore, the first and second filling areas also provide waterproofing. A repair layer is placed above the first and second filling areas. This repair layer has good fertility, facilitating the planting of vegetation to form a vegetation layer, thereby better restoring the area above the open pit. This technology can effectively prevent landslides and other disasters, reduce mine pollution, promote ecosystem restoration, and create green mines. Therefore, the technical solution of this application can effectively solve the problem that open-pit mining is prone to geological disasters and threatens underground production in related technologies.

[0007] Furthermore, the second filling area includes a plurality of first sub-regions arranged sequentially along a direction from away from the work area to closer to the work area.

[0008] Furthermore, a retaining wall and an overflow pipe are provided between the first filling area and the second filling area. The overflow pipe includes a horizontal pipe section and a vertical pipe section. The horizontal pipe section extends toward the second filling area and is located at the bottom of the vertical pipe section.

[0009] Furthermore, the filling structure also includes multiple third filling areas located above the first and second filling areas and below the repair layer. The bottom of the third filling area is higher than the highest point of the fractured rock mass. The third filling area is filled with multiple layers of fourth grout, the strength of the second grout is greater than the strength of the fourth grout, and the third filling area includes multiple second sub-areas arranged sequentially in a direction from away from the working area to close to the working area.

[0010] Furthermore, the first filling area includes a plurality of third sub-regions arranged in a vertical direction, wherein the inner side of the upper third sub-region in two adjacent third sub-regions is farther from the center of the open pit than the inner side of the lower third sub-region.

[0011] Furthermore, the remediation layer includes, from bottom to top, a mineral-soil mixture layer, an acid-reducing layer, and a matrix layer, with the vegetation layer planted on the matrix layer.

[0012] According to another aspect of the present invention, a method for filling an open pit is provided, comprising: filling the bottom of the open pit with a first slurry to form an isolation layer; dividing the open pit into a first filling area adjacent to a fractured rock slope and a second filling area outside the first filling area; forming multiple first filling layers by filling the first filling area with a second slurry first and then filling the second filling area with a third slurry at the same height, wherein the strength of the second slurry is greater than the strength of the third slurry and the strength of the first slurry is greater than the strength of the second slurry; and providing a repair layer above the topmost first filling layer.

[0013] Applying the technical solution of this invention, when filling an open pit, a first high-strength slurry is first filled at the bottom of the pit to form an isolation layer. This isolation layer can seal the hydraulic channels between the open pit and the underground mining system, preventing rainwater from seeping into the ground and threatening underground production. Then, the area above the isolation layer is divided into a first filling area adjacent to the fractured rock slope and a second filling area away from the fractured rock slope. Different strength slurries are filled in each area, resulting in higher strength in the first filling area and relatively lower strength in the second filling area. This reduces costs while ensuring the overall strength of the filling structure. Furthermore, layering the first and second filling areas effectively reduces construction difficulty and ensures construction safety compared to whole filling. In addition, the first and second filling areas further enhance waterproofing. Finally, a repair layer with good fertility is placed above the top first filling layer to facilitate vegetation planting and form a vegetation layer, thereby better restoring the area above the open pit. This technology can effectively prevent landslides and other disasters, reduce mine pollution, promote ecosystem restoration, and create green mines. Therefore, the technical solution of this application can effectively solve the problem that open-pit mining is prone to geological disasters and threatens underground production in related technologies.

[0014] Furthermore, the step of filling the second filling area with the third slurry at the same height includes: dividing the second filling area into a plurality of first sub-regions along the direction away from the working area to the direction closer to the working area; and sequentially filling the plurality of first sub-regions along the direction away from the working area to the direction closer to the working area.

[0015] Furthermore, before the step of filling the first filling area with the second slurry, the method further includes: setting up a retaining wall and an overflow pipe between the first filling area and the second filling area.

[0016] Furthermore, the step of setting up a retaining wall and an overflow pipe between the first filling area and the second filling area includes: placing an L-shaped pipe including a horizontal pipe section and a vertical pipe section between the first filling area and the second filling area, with the horizontal pipe section facing the second filling area and the horizontal pipe section located at the bottom of the vertical pipe section; forming a retaining wall by piling up waste rock, with the retaining wall located above the horizontal pipe section and on one side of the vertical pipe section.

[0017] Furthermore, between the steps of forming multiple first filling layers and setting a repair layer above the topmost first filling layer, the method further includes: filling multiple second filling layers above the topmost first filling layer with a fourth slurry, wherein the strength of the fourth slurry is less than the strength of the second slurry.

[0018] Furthermore, the step of filling a fourth slurry above the topmost first filling layer to form a second filling layer includes: dividing the area above the topmost first filling layer into multiple second sub-regions along the direction away from the working area to the direction closer to the working area; and sequentially filling the multiple second sub-regions along the direction away from the working area to the direction closer to the working area to form a second filling layer.

[0019] Furthermore, the upper surface of the first filling layer, located at the topmost layer, is higher than or level with the highest point of the fractured rock mass.

[0020] Furthermore, the step of setting a repair layer above the topmost first filling layer includes: setting a mineral-soil mixture layer above the topmost first filling layer; setting an acid-reducing layer above the mineral-soil mixture layer; and setting a matrix layer above the acid-reducing layer.

[0021] Furthermore, the thickness of the mineral-soil mixture layer is between 10 cm and 20 cm; and / or, the acid-reducing layer includes slaked lime, with an application rate of 1.5 to 2.0 kg / m³. 2 ; and / or, the substrate layer comprises a mixture of farmyard manure and fermented rice husks, applied at a rate of 3.5 to 7.5 kg / m². 2 .

[0022] Furthermore, methods for filling open pits also include: tilling the substrate layer; and creating a vegetation community system using trees, shrubs, and grasses. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 A lateral cross-sectional view of an embodiment of the filling structure of the open pit according to the present invention is shown;

[0025] Figure 2 It shows Figure 1 A magnified view of point A in the filled structure;

[0026] Figure 3 It shows Figure 1 A transverse cross-sectional view of the infill structure; and

[0027] Figure 4 A flowchart illustrating an embodiment of the method for filling an open pit according to the present invention is shown.

[0028] The above figures include the following reference numerals:

[0029] 10. Isolation layer; 20. First filling area; 21. Third sub-area; 30. Second filling area; 31. First sub-area; 32. Pumping station area; 40. First filling layer; 50. Repair layer; 51. Mineral soil mixture layer; 52. Acid removal layer; 53. Matrix layer; 60. Working area; 71. Retaining wall; 72. Overflow pipe; 721. Horizontal pipe section; 722. Vertical pipe section; 80. Third filling area; 81. Second sub-area. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0032] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0033] like Figure 1 As shown, the filling structure of the open pit in this embodiment includes: an isolation layer 10, a first filling area 20, a second filling area 30, a repair layer 50, and a vegetation layer. The isolation layer 10 is located at the bottom of the open pit and is filled with a first slurry. The first filling area 20 is located above the isolation layer 10 and adjacent to the fractured rock slope, and is filled with multiple layers of a second slurry, the strength of which is greater than that of the second slurry. The second filling area 30 is located above the isolation layer 10 and includes the area within the open pit excluding the first filling area 20, and is filled with multiple layers of a third slurry, the strength of which is greater than that of the third slurry. The repair layer 50 is located above the first filling area 20 and the second filling area 30. The vegetation layer is planted on the repair layer 50.

[0034] Applying the technical solution of this embodiment, a first slurry with higher strength is used to fill the bottom of the open pit to form an isolation layer 10. The isolation layer 10 covers the bottom of the open pit, which can block the hydraulic channel between the open pit and the underground mining system, preventing rainwater and other substances from seeping into the ground and threatening underground production. A first filling area 20 and a second filling area 30 are set above the isolation layer 10 to fill the open pit. Specifically, the first filling area 20 is set close to the slope of the fractured rock mass, and the second filling area 30 is set away from the slope of the fractured rock mass (that is, the second filling area is only adjacent to the slope of the intact rock mass and the first filling area 20). The first filling area 20 is filled with a second slurry with higher strength, which makes the strength of the first filling area 20 higher after filling, while the strength of the second filling area 30 is relatively weaker after filling. This can reduce costs while ensuring the overall strength of the filling structure. Since the height and planar area of ​​the open pit are generally large, it is difficult to construct the open pit as a whole. In this embodiment, the first filling area 20 and the second filling area 30 are filled in layers, which can effectively reduce the construction difficulty. Furthermore, the first filling area 20 and the second filling area 30 further enhance the waterproofing effect. The repair layer 50 is positioned above the first filling area 20 and the second filling area 30. The repair layer 50 has good fertility, facilitating the planting of vegetation to form a vegetation layer, thereby better restoring the ecological environment above the open-pit area. This effectively prevents the formation of disasters such as landslides, reduces mine pollution, promotes ecosystem restoration, and creates a green mine. Therefore, the technical solution of this embodiment effectively solves the problem in related technologies where open-pit mining easily causes geological disasters and threatens underground production.

[0035] Specifically, the phrase "the strength of the second slurry is greater than the strength of the third slurry" means that the strength of the filler formed by the second slurry is greater than the strength of the filler formed by the third slurry. The phrase "the second filling area 30 includes the area within the open pit excluding the first filling area 20" refers to the area within the open pit excluding the first filling area 20 in the transverse direction.

[0036] In addition, the isolation layer 10 can also prevent the acidity of metal sulfides, pollutants and accumulated water from the bottom of the pit from rising back up.

[0037] like Figure 1As shown, in this embodiment, the second filling area 30 includes a plurality of first sub-areas 31 arranged sequentially along a direction from away from the working area 60 to closer to the working area 60. The working area 60 is the area where equipment such as filling equipment and pumping equipment are placed. Dividing the second filling area 30 into a plurality of first sub-areas 31 allows for sequential filling along a direction from away from the working area 60 to closer to the working area 60, reducing the operational difficulty during filling. Simultaneously, during the filling process, overflow water from the slurry and precipitation can collect in the first sub-area 31 closer to the working area 60. Once the water has collected to a certain extent, it can be pumped out and discharged using a pump (e.g., a floating pump station installed in the first sub-area 31). Compared to storing water in other locations within the open pit, this arrangement makes it easier to pump out the stored water.

[0038] When planning a mining area, work zone 60 will be located in a better rock mass area around the open-pit mine, away from areas with poor rock mass (which are prone to fracture during mining) to ensure the safety of personnel and equipment.

[0039] like Figure 1 and Figure 2 As shown, a baffle wall 71 and an overflow pipe 72 are provided between the first filling area 20 and the second filling area 30. The overflow pipe 72 includes a horizontal pipe section 721 and a vertical pipe section 722. The horizontal pipe section 721 extends towards the second filling area 30 and is located at the bottom of the vertical pipe section 722. The baffle wall 71 can restrict the flow of the second slurry, allowing the second slurry to remain within the first filling area and gradually solidify. During the filling process, the overflow pipe 72 can guide the overflow water generated by the second slurry into the second filling area 30 that has not yet been filled, and allow the overflow water to collect in the first sub-area 31 near the working area 60, and finally be pumped out by the water pump. Specifically, when setting up the baffle wall 71 and the overflow pipe 72, the overflow pipe 72 is first placed in a predetermined position, and then the baffle wall 71 is set up, thereby fixing the overflow pipe 72 through the baffle wall 71.

[0040] Specifically, each filling layer in the first filling area 20 is provided with a baffle 71 and an overflow pipe 72 on the side near the second filling area 30 (the number of overflow pipes 72 can be one or more). In each first sub-area 31 except the one closest to the working area 60, each filling layer is provided with a baffle 71 and an overflow pipe 72 on the side near the working area 60.

[0041] During filling, the first filling layer (the bottommost filling layer) in the first filling area 20 can be filled first. Then, the first filling layer of multiple first sub-areas 31 can be filled sequentially in the direction away from the working area 60 and towards the working area 60. After that, the second filling layer in the first filling area 20 can be filled, and the second filling layer of multiple first sub-areas 31 can be filled sequentially in the direction away from the working area 60 and towards the working area 60, and so on. This can effectively reduce the construction difficulty, accelerate dehydration, and allow the filled parts to solidify quickly to facilitate the subsequent filling of the next layer.

[0042] In this embodiment, the filling structure further includes multiple third filling regions 80 disposed above the first filling region 20 and the second filling region 30 and below the repair layer 50. The bottom of the third filling region 80 is higher than the highest point of the fractured rock mass. The third filling region 80 is filled with multiple layers of fourth slurry, the strength of the second slurry being greater than the strength of the fourth slurry. The third filling region 80 includes multiple second sub-regions 81 sequentially disposed along the direction from away from the working area 60 to close to the working area 60. That is, for the region located above the fractured rock mass (i.e., the region corresponding to the intact rock mass), the strength after filling is relatively weaker, which can effectively reduce costs. The filling method of the third filling region 80 can refer to the filling method of the first filling region 20 and the second filling region 30, and will not be described again here.

[0043] It should be noted that the "fractured rock mass" mentioned above refers to rock masses classified as Class I to III according to the rock mass classification standard, while the "intact rock mass" mentioned above refers to rock masses classified as Class IV and V according to the rock mass classification standard.

[0044] In addition, each filling layer in each second sub-area 81, except for the one closest to the work area 60, is equipped with a retaining wall 71 and an overflow pipe 72 on the side closest to the work area 60 to collect slurry overflow water and atmospheric precipitation into the second sub-area 81 closest to the work area 60. After the water has collected to a certain extent, it can be pumped out and discharged using a water pump (for example, by setting up a floating pump station in the second sub-area 81). This arrangement makes it easier to pump out the stored water compared to storing it in other locations in the open pit.

[0045] like Figure 1 As shown, the first filling area 20 includes multiple third sub-areas 21 arranged vertically. In two adjacent third sub-areas 21, the inner side of the upper third sub-area 21 is farther from the center of the open pit than the inner side of the lower third sub-area 21. Since the slope of the open pit gradually slopes outward from bottom to top, setting the multiple third sub-areas 21 to be staggered outward from bottom to top also reduces the amount of second slurry used while ensuring strength, thus lowering costs.

[0046] It should be noted that the terms "inner" and "outer" mentioned above are relative to the open pit; that is, the area closer to the center of the open pit is the inner area, and the area farther from the center of the open pit is the outer area.

[0047] like Figure 1 As shown, the repair layer 50 includes a mineral soil mixture layer 51, an acid-reducing layer 52, and a matrix layer 53 arranged sequentially from bottom to top, and the vegetation layer is planted on the matrix layer 53.

[0048] like Figure 4 As shown, this application also provides a method for filling an open pit. The method for filling an open pit in this embodiment includes:

[0049] Step S10: Fill the bottom of the open pit with the first slurry to form an isolation layer 10;

[0050] Step S20: Divide the open pit into a first filling area 20 adjacent to the fractured rock slope and a second filling area 30 located outside the first filling area 20;

[0051] Step S30: Multiple first filling layers 40 are formed by filling the first filling area 20 with the second slurry first, and then filling the second filling area 30 with the third slurry at the same height. The strength of the second slurry is greater than that of the third slurry, and the strength of the first slurry is greater than that of the second slurry.

[0052] Step S50: Place a repair layer 50 above the first fill layer 40 located at the top layer.

[0053] Applying the technical solution of this embodiment, when filling the open pit, step S10 is first executed, where a first slurry with high strength is filled at the bottom of the open pit to form an isolation layer 10. The isolation layer 10 can seal the hydraulic channel between the open pit and the underground mining system, preventing rainwater and other substances from seeping into the ground and threatening underground production. Then, step S20 is executed, dividing the area above the isolation layer 10 into a first filling area 20 adjacent to the fractured rock slope and a second filling area 30 away from the fractured rock slope. Different strength slurries are then filled in these areas, resulting in higher strength in the first filling area 20 and relatively weaker strength in the second filling area 30 after filling. This reduces costs while ensuring the overall strength of the filling structure. Furthermore, layering the first filling area 20 and the second filling area 30, compared to whole filling, effectively reduces construction difficulty and ensures construction safety. In addition, the first filling area 20 and the second filling area 30 further provide a waterproofing effect. Next, step S50 is executed, where a restoration layer 50 is placed above the topmost first filling layer 40. The restoration layer 50 has good fertility, facilitating the planting of vegetation to form a vegetation layer, thereby better restoring the ecological environment above the open-pit area. This effectively prevents landslides and other disasters, reduces mine pollution, promotes ecosystem restoration, and creates a green mine. Therefore, the technical solution of this embodiment effectively solves the problem in related technologies where open-pit mining easily causes geological disasters and threatens underground production.

[0054] Specifically, the step of filling the second filling area 30 with the third slurry at the same height includes: dividing the second filling area 30 into multiple first sub-areas 31 along the direction away from the working area 60 and towards the working area 60; and sequentially filling the multiple first sub-areas 31 along the direction away from the working area 60 and towards the working area 60. The working area 60 is the area where filling equipment, pumping equipment, etc., are placed. Dividing the second filling area 30 into multiple first sub-areas 31 and filling them sequentially along the direction away from the working area 60 and towards the working area 60 reduces the difficulty of the filling operation. Simultaneously, during the filling process, slurry overflow water and atmospheric precipitation can collect in the first sub-area 31 near the working area 60. After collecting to a certain extent, the water can be pumped out and discharged using a pump (e.g., a floating pump station set up in the first sub-area 31). Compared to storing water in other locations in the open pit, this arrangement makes it easier to pump out the stored water. Specifically, a water storage tank can be set up in the work area 60 to store the water pumped from the open pit before it is transported away.

[0055] Before the step of filling the first filling area 20 with the second slurry, the method further includes: setting up a baffle 71 and an overflow pipe 72 between the first filling area 20 and the second filling area 30. The baffle 71 can restrict the flow of the second slurry, allowing it to remain within the first filling area and gradually solidify. During the filling process, the overflow pipe 72 can guide the overflow water generated by the second slurry into the second filling area 30 that has not yet been filled, and allow the overflow water to collect in the first sub-area 31 near the working area 60, and finally be pumped out by a water pump.

[0056] The steps of setting up a retaining wall 71 and an overflow pipe 72 between the first filling area 20 and the second filling area 30 include: placing an L-shaped pipe including a horizontal pipe section 721 and a vertical pipe section 722 between the first filling area 20 and the second filling area 30, with the horizontal pipe section 721 facing the second filling area 30 and located at the bottom of the vertical pipe section 722; forming the retaining wall 71 by piling up waste rock, with the retaining wall 71 located above the horizontal pipe section 721 and on one side of the vertical pipe section 722; setting the vertical pipe section 722 of the L-shaped overflow pipe 72 on the side of the retaining wall 71 close to the first filling area 20, and setting the horizontal pipe section 721 of the L-shaped overflow pipe 72 below the vertical pipe section 722 and extending it towards the second filling area 30, so that the overflow water generated by the second slurry is guided into the second filling area 30 that has not yet been filled. Specifically, when setting up the retaining wall 71 and the overflow pipe 72, the overflow pipe 72 is first placed in a predetermined position, and then the retaining wall 71 is set up, thereby fixing the overflow pipe 72 through the retaining wall 71.

[0057] Specifically, each first filling layer 40 within the first filling area 20 is equipped with a retaining wall 71 and an overflow pipe 72 (the number of overflow pipes 72 can be one or more) on the side closest to the second filling area 30. Similarly, each first filling layer 40 within each first sub-area 31 (except for the area closest to the working area 60) is equipped with a retaining wall 71 and an overflow pipe 72 on the side closest to the working area 60. This allows overflow water from the slurry and atmospheric precipitation to be channeled through the overflow pipes 72 to the next area to be filled, ultimately allowing the water to collect in the first sub-area 31 closest to the working area 60 and drain out of the open pit.

[0058] Between the steps of forming multiple first filling layers 40 and setting a repair layer 50 above the topmost first filling layer 40, the method further includes: Step S40: Multiple second filling layers are formed by repeatedly filling a fourth slurry above the topmost first filling layer 40, wherein the strength of the fourth slurry is less than that of the second slurry. Specifically, the upper surface of the topmost first filling layer 40 is higher than or level with the highest point of the fractured rock mass. Using a lower-strength fourth slurry to fill the area above the first filling area 20 and the second filling area 30 can save costs while ensuring filling strength.

[0059] The step of filling the first filling layer 40 with a fourth slurry to form a second filling layer includes: dividing the area above the first filling layer 40 into multiple second sub-regions 81 along the direction away from the working area 60 and towards the working area 60; and sequentially filling the multiple second sub-regions 81 along the direction away from the working area 60 and towards the working area 60 to form a second filling layer. Dividing the area above the first filling layer 40 into multiple second sub-regions 81 and sequentially filling them along the direction away from the working area 60 and towards the working area 60 can effectively reduce construction difficulty and can collect overflow water and atmospheric precipitation into the second sub-region 81 near the working area 60 for pumping out together, facilitating pumping operations.

[0060] Specifically, the height of the first filling layer 40 and the second filling layer is between 3 mm and 3.5 m. Preferably, the height of both the first filling layer 40 and the second filling layer is 3 m.

[0061] The step of setting up a restoration layer 50 above the topmost first filling layer 40 includes: setting up a mineral soil mixture layer 51 above the topmost first filling layer 40; setting up an acid-neutralizing layer 52 above the mineral soil mixture layer 51; and setting up a matrix layer 53 above the acid-neutralizing layer 52. The aforementioned mineral soil mixture layer 51 refers to the waste mineral soil mixture from the mining area. Compared to directly using soil layers, using the waste mineral soil mixture from the mining area can treat the waste mineral soil while saving soil resources and reducing costs, especially for mines in southern my country where soil resources are scarce, making it highly economical. Since the mineral soil mixture layer 51 in metal mines is acidified soil, setting up the acid-neutralizing layer 52 on top of the mineral soil mixture layer 51 can neutralize its acidity. Then, a matrix layer 53 suitable for planting vegetation is set up on the acid-neutralizing layer 52 to facilitate the formation of a vegetation layer, thereby better ecologically restoring the area above the open pit.

[0062] Specifically, the thickness of the mineral-soil mixture layer 51 is between 10 cm and 20 cm; the acid-reducing layer 52 includes slaked lime, with an application rate of 1.5 to 2.0 kg / m³. 2The substrate layer 53 comprises a mixture of farmyard manure and fermented rice husks, applied at a rate of 3.5 to 7.5 kg / m³. 2 The application rate of slaked lime within the aforementioned range balances neutralization effect and cost. Farmyard manure provides fertility, and fermented rice husks improve soil permeability, promoting the growth of soil microorganisms and consequently vegetation. Preferably, the mineral-soil mixture layer 51 can be 15cm, 17.5cm, or 20cm thick, and the application rate of slaked lime can be 1.5kg / m³. 2 1.75kg / m 2 Or 2.0 kg / m 2 The application rate of the mixture can be 7.5 kg / m³. 2 5.5kg / m 2 Or 3.5kg / m 2 The ratio of farmyard manure to fermented rice husks in the mixture is between 6:4 and 8:2, preferably 7:3.

[0063] In addition, vegetation restoration can be carried out on the rock slopes from the third filling area 80 to the final ecological restoration boundary using the netting and topsoil spraying method.

[0064] Furthermore, the filling method for the open pit also includes: tilling the substrate layer 53; and creating a vegetation community system using trees, shrubs, and grasses. After tilling the substrate layer 53, various vegetation such as trees, shrubs, and grasses are planted on the substrate layer to ensure the diversity of the formed vegetation and avoid the degradation of the vegetation community later. Specifically, when selecting plants, evergreen plants need to be provided considering the changing seasons, and plant species with stronger ornamental value are selected. Specifically, large and small-sized seedlings from nutrient bags are mixed, with a spacing of 2m between trees and 1.0m between shrubs. The ratio of shrubs to trees is 4:1, and the ratio of trees to flowering plants is 3:1.

[0065] Specifically, the filling method in this embodiment further includes using a floating pump station to drain the water from the open pit during the filling process of the first filling layer 40 and the second filling layer. For example... Figure 3As shown, the floating pump station is located within the pump station area 32. Specifically, when filling each first filling layer 40, the portion within the first filling area 20 is filled first, and then the portion within the first sub-area 31 is filled sequentially in the direction away from the working area 60 and towards the working area 60. Slurry overflow water and atmospheric precipitation will flow from the first filling area 20 to the second filling area 30 under the guidance of the overflow pipe 72, and then from the first sub-area 31 away from the working area 60 to the first sub-area 31 near the working area 60. Finally, the water will collect in the first sub-area 31 near the working area 60. The floating pump station will then drain the water from the open pit into the storage tank above the open pit, and then fill the first sub-area 31 near the working area 60, completing the filling of the first filling layer 40. The filling and drainage methods for each second filling layer are similar to those for the first filling layer 40 and will not be described further here.

[0066] Furthermore, the filling method of this embodiment also includes setting up a drainage ditch around the outside of the open pit. During the rainy season, this can prevent rainwater from the outside of the open pit from accumulating inside.

[0067] The filling method of this application is illustrated below with a specific embodiment of the filling of an open-pit copper mine in Hubei Province:

[0068] This copper mine was historically a combined open-pit and underground mine. Open-pit mining ceased in 2000, and it currently has a volume of approximately 634 × 10⁴ m³. 3 The open-pit mine has a top elevation of approximately +40m and a bottom elevation of approximately -60m, and underground mining has been ongoing since then. The mining area has a typical southern climate, characterized by high humidity and abundant rainfall, primarily concentrated between May and July. The open-pit slopes are mainly composed of gravelly soil (slag), making them prone to landslides and other geological disasters, posing a threat to the mine's safe production. The open-pit bottom consists of fractured ore rock, and during the rainy season, rainwater collected in the open-pit seeps into the underground tunnels, threatening underground safety and increasing mine drainage costs. Therefore, it is urgent to fill the copper mine open-pit to restore its ecological environment.

[0069] First, an isolation layer 10 is installed at the bottom of the open pit. Based on site conditions, considering that there is no underground mining activity in the lower part of the open pit (vertical height approximately 200m), and that the local rock mass at the bottom of the pit is affected by mining blasting vibrations during open-pit production, the sealing project is determined to be from -60m to -39m at the bottom of the open pit, with an isolation layer thickness of 21m. To ensure backfilling quality, grout with a 28-day strength of not less than 3.0MPa is used for backfilling. Backfilling is carried out in one go during a clear weather period. The backfilling sequence is from west to east, first backfilling the western bottom of the pit, then backfilling the eastern bottom (in this embodiment, the fractured rock mass is concentrated on the western slope, and the working area 60 is located on the outer perimeter of the eastern slope; that is, the backfilling sequence is from the direction away from the working area 60 towards the direction closer to the working area 60).

[0070] Subsequently, the first filling area 20 (located in the western part of the open pit), the second filling area 30, and the third filling area 80 were filled in layers and sections. Specifically, the distance between the inner wall of the first filling area 20 (-39m to 0m) and the western sidewall of the open pit is greater than or equal to 30m. High-strength filling material (28-day strength not less than 1.5MPa) was used to fill the first filling area 20. The second filling area 30 (-39m to 0m) and the third filling area 80 (0m to 35m) were filled with a material (28-day strength not less than 0.5MPa). Specifically, the filling direction of each filling layer was from west to east, filling the area (first filling area 20) and the sub-areas (first sub-area 31 and second sub-area 81) one by one. Specifically, during the filling process, retaining walls 71 are set between the first filling area 20 and the second filling area 30, and between adjacent first sub-area 31 and adjacent second sub-area 81. The retaining walls 71 are formed by compacting waste stone, and the retaining walls 71 are 3.5m high and 3m wide at the top.

[0071] Specifically, the aforementioned filling material is a cemented slurry made from tailings produced by the mineral processing plant. The cement-sand ratio of the filling material (first slurry) with a 28-day strength of not less than 3 MPa is 1:4; the cement-sand ratio of the filling material (second slurry) with a 28-day strength of not less than 1.5 MPa is 1:10; and the cement-sand ratio of the filling materials (third and fourth slurries) with a 28-day strength of not less than 0.5 MPa is 1:25. The concentration of the filling material should be maximized; specifically, the concentration of the cemented filling slurry is 68%. Of course, the filling material ratio and concentration can be further optimized based on actual filling effects and filling ratio tests. Since southern my country is a rainy region, filling should be avoided during the rainy season. When filling during the rainy season, the filling area should be reduced, and the surface of the filling body should be covered with rainproof fiber cloth or other protective materials for curing.

[0072] Next, a remediation layer 50 and a vegetation layer are installed above the third filling area 80. First, waste mineral soil from the mining area is used for covering: after transporting the waste mineral soil mixture with the shortest transport distance to the third filling area 80, large pieces of gravel are removed, and the mixture is evenly spread on the surface of the third filling area 80, with a soil mixture cover layer thickness of 15cm. Then, in-situ soil matrix improvement is carried out: a layer of slaked lime is spread or sprayed onto the surface of the waste mineral soil, with an application rate of 1.5kg / m². 2 Then, a layer of a mixture of fresh farmyard manure and fermented rice husks is manually spread as a substrate layer 53, with an application rate of 7.5 kg / m³. 2 Finally, simple manual tilling is carried out. A vegetation community system is then created using trees, shrubs, and grasses. For trees, black locust is selected, with a spacing of 2m between trees. For shrubs, small-leaved privet, lespedeza, purple locust, and forsythia are selected, with a spacing of 1.0m between shrubs. After planting, water thoroughly to settle the roots, and water as needed according to soil conditions. For herbaceous plants, vetiver grass, bahia grass, bermudagrass, pigeon pea, pigweed, lespedeza, white clover, sweet clover, wild chrysanthemum, sulfur cosmos, cosmos, and fleabane are selected at 30g / m². 2 Sow a mixture of seeds.

[0073] During the filling process, floating pump stations will be set up within the open pit (specifically at 32 pump station locations) to drain the accumulated and overflowing water into storage tanks around the pit. Simultaneously, four intercepting ditches will be constructed around the pit (either utilizing existing ditches or constructing new ones), using mortar-grouted rubble masonry. The normal water catchment volume within the open pit is 1700 m³. 3 / d, during a once-in-twenty-year rainstorm, the maximum runoff volume is 52,000 m³. 3 / d, the designed backfill water volume is 311.5m³. 3 / d.

[0074] The technical solution of this embodiment can effectively solve the safety hazards caused by water backflow from the bottom of the pit into the mine, reduce the damage caused by landslides, and at the same time reduce mine environmental pollution and promote ecological restoration, which has important social significance for building green mines. In addition, the above-mentioned filling method has the advantages of being easy to construct, simple in process, and easy to operate.

[0075] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0076] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0077] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A filling structure for an open-pit pit, characterized in that, include: An isolation layer (10) is set at the bottom of the open pit, and the isolation layer (10) is filled with a first slurry; The first filling area (20) is set above the isolation layer (10) and adjacent to the fractured rock slope. The first filling area (20) is filled with multiple layers of second slurry, and the strength of the first slurry is greater than that of the second slurry. The second filling area (30) is disposed above the isolation layer (10). The second filling area (30) includes the area in the open pit other than the first filling area (20). The second filling area (30) is filled with multiple layers of third slurry, and the strength of the second slurry is greater than that of the third slurry. A repair layer (50) is disposed above the first filling area (20) and the second filling area (30); A vegetation layer, planted on the restoration layer (50); The filling structure also includes a plurality of third filling areas (80) disposed above the first filling area (20) and the second filling area (30) and below the repair layer (50). The bottom of the third filling area (80) is higher than the highest point of the fractured rock mass. The third filling area (80) is filled with multiple layers of fourth slurry. The strength of the second slurry is greater than the strength of the fourth slurry. The third filling area (80) includes a plurality of second sub-areas (81) arranged sequentially along the direction away from the working area and towards the working area. The first filling area (20) includes a plurality of third sub-regions (21) arranged in a vertical direction, wherein the inner side of the upper third sub-region (21) of two adjacent third sub-regions (21) is farther away from the center of the open pit than the inner side of the lower third sub-region (21).

2. The filling structure of the open-pit pit according to claim 1, characterized in that, The second filling area (30) includes a plurality of first sub-areas (31) arranged sequentially along a direction away from the work area (60) and towards the work area (60).

3. The filling structure of the open pit according to claim 1, characterized in that, A retaining wall (71) and an overflow pipe (72) are provided between the first filling area (20) and the second filling area (30). The overflow pipe (72) includes a horizontal pipe section (721) and a vertical pipe section (722). The horizontal pipe section (721) extends toward the second filling area (30) and is located at the bottom of the vertical pipe section (722).

4. The filling structure of the open pit according to any one of claims 1 to 3, characterized in that, The repair layer (50) includes a mineral soil mixture layer (51), an acid-reducing layer (52) and a matrix layer (53) arranged sequentially from bottom to top, and the vegetation layer is planted on the matrix layer (53).

5. A method for filling an open pit, used in the filling structure of the open pit according to claim 1, characterized in that, include: The bottom of the open pit is filled with the first slurry to form an isolation layer (10); Within the open pit, a first filling area (20) adjacent to the fractured rock slope and a second filling area (30) located outside the first filling area (20) are divided. Multiple first filling layers (40) are formed by filling the first filling area (20) with the second slurry first and then filling the second filling area (30) with the third slurry at the same height. The strength of the second slurry is greater than that of the third slurry, and the strength of the first slurry is greater than that of the second slurry. A repair layer (50) is provided above the first filling layer (40) located at the top layer; The step between forming multiple first filler layers (40) and setting a repair layer (50) above the topmost first filler layer (40) further includes: Multiple second filling layers are formed by repeatedly filling a fourth slurry above the first filling layer (40) located at the top layer, wherein the strength of the fourth slurry is less than that of the second slurry; The upper surface of the first filling layer (40) located at the top layer is higher than or level with the highest point of the fractured rock mass.

6. The method for filling an open pit according to claim 5, characterized in that, The step of filling the second filling area (30) with the third slurry at the same height includes: The second filling area (30) is divided into a plurality of first sub-regions (31) along the direction from away from the working area (60) to close to the working area (60). The first sub-regions (31) are sequentially filled along a direction from away from the work area (60) to close to the work area (60).

7. The method for filling an open pit according to claim 5, characterized in that, The step of filling the first filling region (20) with the second slurry includes the following steps: A retaining wall (71) and an overflow pipe (72) are provided between the first filling area (20) and the second filling area (30).

8. The method for filling an open pit according to claim 7, characterized in that, The steps of setting up a retaining wall (71) and an overflow pipe (72) between the first filling area (20) and the second filling area (30) include: An L-shaped tube comprising a horizontal tube segment (721) and a vertical tube segment (722) is placed between the first filling area (20) and the second filling area (30), with the horizontal tube segment (721) facing the second filling area (30) and the horizontal tube segment (721) located at the bottom of the vertical tube segment (722); The retaining wall (71) is formed by piling up waste stones. The retaining wall (71) is located above the horizontal pipe section (721) and on one side of the vertical pipe section (722).

9. The method for filling an open pit according to claim 5, characterized in that, The step of filling a second filling layer with a fourth slurry above the first filling layer (40) located at the top layer includes: The area above the first filling layer (40) located at the top layer is divided into a plurality of second sub-regions (81) along the direction from away from the working area (60) to close to the working area (60). A plurality of second sub-regions (81) are sequentially filled in a direction from away from the working area (60) to close to the working area (60) to form a second filling layer.

10. The method for filling an open pit according to any one of claims 5 to 8, characterized in that, The step of setting a repair layer (50) above the first filler layer (40) located at the top layer includes: A mineral soil mixture layer (51) is provided above the first filling layer (40) located at the top layer. An acid-reducing layer (52) is provided above the mineral-soil mixture layer (51); A matrix layer (53) is disposed above the acid-reducing layer (52).

11. The method for filling an open pit according to claim 10, characterized in that, The thickness of the mineral-soil mixture layer (51) is between 10 cm and 20 cm; and / or, The acid-reducing layer (52) comprises slaked lime, and the amount of slaked lime applied is 1.5 to 2.0 kg / m³. 2 ; and / or, The substrate layer (53) comprises a mixture of farmyard manure and fermented rice husks, applied at a rate of 3.5 to 7.5 kg / m³. 2 .

12. The method for filling an open pit according to claim 10, characterized in that, The method for filling the open pit also includes: Till the substrate layer (53); Trees, shrubs and grasses are used to create a vegetation community system.

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