A combined recycling process for the base column of a pressure-free arch triangular prism

Abstract

This application discloses a combined recovery process for the bottom column of a triangular prism under a pressure-free arch, belonging to the field of mining engineering technology. It includes: arranging a bottom column drilling tunnel (5) in the bottom column (1) directly below the triangular prism (2), and constructing upward parallel medium-deep holes (6) to blast the bottom column ore body; arranging parallel drilling tunnels (4) symmetrically on both sides of the triangular prism (2), and forming triangular arch-shaped fan-shaped medium-deep holes (3) by constructing oblique upwards in opposite directions, retaining the upper ore body to construct a pressure-free arch (8); the pressure-free arch (8) and the tailings cemented backfill (9) enhance the bearing stability; this application uses the pressure-free arch structure to axially transfer the upper load to the sidewall surrounding rock, reducing stress concentration in the goaf; the cemented backfill increases the bearing strength under the cooperation of the pressure-free arch foot; the cooperation avoids the resource waste caused by the overall retention of the triangular prism in the traditional process and reduces the support cost.

Description

Technical Field

[0001] This invention belongs to the field of mining engineering technology, and in particular relates to a combined recycling process for the bottom column of a pressure-free arch triangular prism. Background Technology

[0002] In the mining industry, the bottom pillar, as a core component supporting the stability of the stope structure, often forms a key part of ore body recovery together with the triangular pillar formed above it. In traditional mining methods, the recovery of the bottom pillar and the triangular pillar typically employs a step-by-step operation: first, the upper triangular pillar is recovered through methods such as medium-deep hole blasting or manual chiseling, and then the bottom pillar is processed separately. However, this step-by-step recovery strategy requires the triangular pillar to be outside the filling material; when the triangular pillar is inside the filling material, there is no effective method for jointly recovering the triangular pillar and its underlying bottom. Summary of the Invention

[0003] In view of the technical problems existing in the background art, this application provides a combined recycling process for the base column of a triangular prism under a pressure-free arch, including:

[0004] S1. Construct cutting risers in the middle or end of the mining area and supplement upward parallel medium-deep holes for grooving operations;

[0005] S2. Arrange a bottom column rock drilling tunnel inside the bottom column directly below the triangular prism;

[0006] S3. Construct upward parallel medium-deep holes in the bottom pillar rock drilling tunnel;

[0007] S4. Blasting the bottom pillar ore body to extract ore;

[0008] S5. Parallel drilling tunnels are arranged on both sides of the triangular prism;

[0009] S6. In the parallel rock drilling tunnels on both sides of the upper triangular column, diagonally upward drilling is carried out to form a triangular arch-shaped fan-shaped medium-deep hole, and no blasting holes are carried out in the upper part of the ore body of the triangular column.

[0010] S7. Blasting the upper triangular prism to extract ore;

[0011] S8. Unblasted triangular prism ore body is retained as a pressure-free arch under the filling body;

[0012] S9. Conduct tailings cementing and backfilling operations within the mining area to form a cemented backfill body.

[0013] In some implementations, in step S5, the parallel rock drilling tunnel has a width of 2.6 meters and a height of 2.6 meters.

[0014] In some embodiments, in step S6, the angle between the deep hole in the sector and the top plate is 42 degrees.

[0015] In some embodiments, in step S6, the spacing between the deep holes in the sector is 1.4 meters, and the distance between the bottom holes is 1.5 meters.

[0016] In some implementations, in step S2, two bottom pillar drilling tunnels are arranged in parallel, and the bottom pillars are correspondingly divided into two mining areas.

[0017] In some implementations, in step S2, the bottom pillar rock drilling tunnel has a width of 2.6 meters and a height of 2.6 meters.

[0018] In some implementations, in step S3, the two sections of the base pillar are blasted separately.

[0019] In some implementations, in step S4, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck extraction.

[0020] In some implementations, in step S7, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck extraction.

[0021] In some implementations, in step S6, a YGZ-90 device is used to drill rock and form a sloping fan-shaped medium-deep hole.

[0022] This invention provides a pressure-free, integrated recovery process for the bottom pillar of a triangular prism. Through precise positioning of the cutting riser and slotting blasting in S1, the problem of irregular initial free surface formation is solved, creating geometric conditions for the coordinated blasting of the bottom pillar and triangular prism, thus avoiding the problem of blasting energy dispersion caused by boundary loss of control. Through the positioning and arrangement of the bottom pillar drilling tunnels in S2 and the coordinated construction of upward parallel medium-deep holes in S3, the problem of drilling path deviation in the bottom pillar ore body is solved, thereby optimizing the blasting focusing effect, improving the recovery efficiency of the bottom pillar ore body, and forming a compensation space, providing a stable base for the triangular prism blasting. Through the priority blasting of the bottom pillar ore body in S4, the working space is released and the disturbance accumulation of subsequent triangular prism operations is reduced, which helps maintain the temporary stability of the stope. Through the symmetrical arrangement of parallel drilling tunnels on both sides of the triangular prism in S5 and S... The mirror-image construction of the upward-sloping fan-shaped deep holes in section 6 overcomes the limitation of rigid drill rods in drilling curved sections, thereby forcing the ore body to fracture along the preset triangular facets to form a geometrically regular arched profile, which is conducive to actively constructing the basic form of the pressure-free arch structure. By retaining the upper part of the ore body of the triangular prism in section S7 and selectively blasting the middle and lower parts, the contradiction between recovery rate and backfill stability is resolved. Furthermore, the continuity of the intact rock mass is used to form a self-supporting triangular arch, which is conducive to axially transferring the upper load to the sidewall rock rather than the goaf. By retaining the unblasted triangular prism as a backfill body in section S8 and supplementing it with tailings cemented backfill in section S9, the defect of insufficient bearing capacity of artificial backfill body when the lower part is completely mined out is solved. Furthermore, the radial constraint of the arch foot and the sealing of the cemented body enhance the overall compressive strength, which is conducive to achieving the unity of long-term stability of the stope and efficient resource recovery. Traditional processes cannot balance the contradiction between triangular prism recovery and backfill stability, and the need to retain the triangular prism as a whole leads to resource waste. This scheme uses directional blasting to form a pressure-free arch structure, allowing the residual ore body to form a pressure-free arch structure. While recovering resources in the lower part of the bottom pillar and triangular pillar, the mechanical properties of the arch structure are used to transfer stress to the surrounding rock, and the combined cemented filling achieves a dual improvement in stability and recovery rate.

[0023] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0025] Figure 1This is a schematic diagram of the overall process layout for the combined recycling of the bottom column of the triangular prism under the pressure arch, as provided in the embodiments of this application.

[0026] Figure 2 This is a schematic diagram of the bottom column portion of the combined recovery process of the bottom column of the triangular prism under the pressure arch provided in the embodiments of this application;

[0027] Figure 3 This is a schematic diagram of the triangular column portion of the combined recovery process of the bottom column of the triangular column under the pressure arch provided in the embodiments of this application;

[0028] Figure 4 This is a schematic diagram of the structure after filling in a combined recycling process for the bottom column of a triangular prism under a pressure arch, as provided in an embodiment of this application.

[0029] Explanation of reference numerals in the attached diagram: 1. Bottom pillar; 2. Triangular pillar; 3. Fan-shaped medium-deep hole; 4. Parallel drilling tunnel; 5. Bottom pillar drilling tunnel; 6. Upward parallel medium-deep hole; 7. Bottom pillar post-mining goaf; 8. Pressure-free arch; 9. Cemented backfill. Detailed Implementation

[0030] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0032] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0033] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0034] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0035] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0036] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0037] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0039] Reference Figures 1 to 4 A combined recycling process for a pressure-free arch with 8 lower triangular prisms, 2 base columns, and 1 bottom column includes:

[0040] S1. Construct cutting raises in the middle or end of the stope, and supplement with upward parallel medium-deep holes for slotting operations. This step defines the blasting starting point by creating an initial channel. Its specific function is to provide a clear spatial boundary for subsequent blasting, achieving a slotting structure to guide the uniform distribution of blasting energy. The aim is to avoid irregular cracks during blasting. Stable slotting is achieved by using the cutting raise as a central positioning point and the parallel arrangement of upward parallel medium-deep holes, thereby improving blasting efficiency and safety. For example, use a total station to mark the location of the cutting raises (cross-section ≥ 2m × 2m) in the middle or end of the stope, ensuring it matches the design profile. The height is usually designed to be consistent with the segment height. Then, medium-deep hole blasting is employed. The well is constructed in one operation. Specifically, a large-diameter (75 mm) hole is drilled in the center as a free face. Four charging holes (45-50 mm in diameter) are arranged around it in a columnar pattern with a spacing of 500 mm. The detonation is carried out using a combination of detonating cord and detonating wire, with a micro-delay interval of 25-50 milliseconds, forming a cutting well. After that, using the cutting well as a free face, parallel medium-deep holes (76-100 mm in diameter) are drilled upwards with a row spacing of 1.2-1.5 meters and a bottom-to-bottom distance of 1.3-1.5 times the row spacing. Then, blasting is carried out in stages. The first blasting is used to cut the slotted area to form a compensation space. Then, the auxiliary holes and surrounding holes are blasted to ensure that the well wall flatness error is ≤±0.5m, thus completing the slotting operation.

[0041] S2. A bottom pillar drilling tunnel 5 is arranged within the bottom pillar 1 directly below triangular prism 2. By setting up tunnels at key locations, the blasting focus is controlled, and a working face is formed, providing a positioning basis for the drilling operation in S3. This aims to ensure that the bottom blasting is directly aligned with triangular prism 2. The reasonable arrangement of the bottom pillar drilling tunnel 5 optimizes the drilling path, covering the ore body of bottom pillar 1, thereby reducing drilling deviation and saving time. Simultaneously, it compensates for the ore falling from bottom pillar 1 during blasting. For example, a drilling tunnel (2.6m x 2.6m cross-section) is arranged within the bottom pillar 1 directly below triangular prism 2, perpendicular to the ore body strike, ensuring the stability of the tunnel roof.

[0042] S3. Construct upward parallel medium-deep holes 6 within the bottom pillar drilling tunnel 5. This step generates a series of parallel holes for charging explosives through optimized drilling setup, aiming to uniformly break up the ore body. The parallel arrangement of the holes achieves a synergistic blasting effect, generating overlapping pressure waves to enhance ore body fracturing, thereby increasing blast coverage and reducing residual ore. For example, upward parallel medium-deep holes 6 (inclination angle 75-90 degrees) are drilled within the drilling tunnel, with a row spacing of 1.5 meters, and the hole depth reaches the boundary between the bottom pillar 1 and the triangular prism 2.

[0043] S4. Blasting to extract ore from the bottom pillar 1 ore body; This step involves blasting to release the ore from the bottom pillar 1. Blasting removes the ore body from the bottom pillar 1 to recover the minerals and free up bottom space, forming the post-mining void 7 of the bottom pillar 1. This prioritizes the processing of the bottom pillar 1 area for efficient extraction. It is placed before the blasting of the triangular pillar 2 (S7) to provide a stable base for subsequent operations. Since the triangular pillar 2 relies on bottom support above the bottom pillar 1, blasting the bottom pillar 1 first avoids premature disturbance of the triangular pillar 2, while maintaining temporary stability in the stope, facilitating the next stage of operations, ensuring sufficient working space for subsequent blasting processes, and reducing the structural risk of instantaneous disturbance. For example, if the compensation coefficient after charging is ≥1.35 (compensation space volume / blasting volume), blasting can be performed in one go; otherwise, blasting should be done in stages (first the middle hole, then the side holes). After blasting, electric scrapers or loaders should be used to collect the ore in a timely manner to avoid blockage.

[0044] S5. Parallel drilling tunnels 4 are arranged on both sides of the triangular prism 2. The purpose of this step is to provide a straight working channel for the drill bit to achieve precise oriented drilling. Because the drilling equipment cannot bend or turn, it must rely on symmetrically arranged tunnels to ensure the straightness of the drilling path to form symmetrical triangular arch blast holes. This creates the physical conditions for the subsequent upward-sloping fan-shaped medium-deep hole 3 construction in S6. The rigid drill rod of the drilling rig can only advance in a straight line, while the symmetrical working face formed by the tunnels on both sides allows the drill bit to work simultaneously from both directions along a straight path. This allows for the precise construction of an array of opposing inclined boreholes within the triangular prism 2 ore body, avoiding the need for curved drilling. For example, with the central axis of the triangular prism 2 ore body as the reference, parallel drilling tunnels 4 are symmetrically arranged on both sides, with a spacing of 1.2 times the width of the ore body. The cross-sectional dimensions of the parallel drilling tunnels 4 are 2.6 meters wide and 2.6 meters high.

[0045] S6. In the parallel drilling tunnels 4 on both sides of the upper triangular prism 2, diagonally upward drilling is carried out to form triangular arch-shaped fan-shaped medium-deep holes 3, leaving the upper part of the ore body of the triangular prism 2 un-drilled. The diagonally drilled holes naturally form a triangular arch layout in space (low on both sides, high in the center). When blasting occurs, the explosive forces on both sides converge and collide at the central axis of the triangular prism 2, forcing the ore body to fracture along the preset triangular face through the superposition effect of shock waves, actively shaping a geometrically regular three-dimensional arch structure. The diagonally upward drilling and selective preservation of the upper part... The ore body forms a complete arched outline, directly forming a pressure-free arch structure with stronger compressive strength under gravity; for example, the inclination angle of the blast holes is inclined towards the central axis of the ore body, and the inclination angle of the blast holes is taken as the angle between the blast hole and the roof plate of 42 degrees. The spacing between the blast holes is 1.2 meters to 1.5 meters, and the depth of a single hole is determined by multiplying the tunnel spacing by half of sin42° (i.e., the inclination angle of the blast holes). The inclination angles of the blast holes on both sides of the tunnel are mirror symmetrical (error ≤ ±0.3°). The position of the borehole is laid out by a laser positioning instrument (accuracy ±2 cm).

[0046] S7. Blast and extract ore from the upper triangular pillar 2. Exemplarily, first blast the ore bodies on both sides of the triangular pillar 2, and then process the middle part. Use "pin"-shaped millisecond blasting and use an electric scraper or a load-haul-dump machine to concentrate the ore extraction to avoid blockage.

[0047] S8. Retain the ore body of the unblasted triangular pillar 2 as the pressure-free arch 8 under the filling body. Its core value lies in solving the contradiction of both recovering the ore body of the triangular pillar 2 and maintaining the stability of the original filling area by controlling the residual shape of the ore body. The traditional process directly retains the entire triangular pillar 2 to maintain the stability of the upper filling body because it cannot balance the contradiction between the recovery rate and stability. However, based on the constraint of not drilling blast holes in the upper ore body of the triangular pillar 2 in S6, the blasting in this step only acts on the middle and lower parts of the triangular pillar 2, and the upper complete and continuous ore body naturally remains as a triangular arch structure. The key supporting part that is retained has strong bearing capacity than the artificial filling body due to the continuity of the intact rock mass, which is sufficient to support the weight of the upper filling body, thus ensuring the safety of personnel and equipment in the lower stope. At the same time, the deliberately retained triangular arch shape is not randomly residual, but is forced to rupture along the preset triangular surface by the symmetric blast holes in S5 and S6 (drilling obliquely from both sides) to form a geometrically regular arched contour. This equilateral triangular arch generates axial pressure transmission under the gravity load: the pressure at the arch top is transmitted along both arch feet to the surrounding rock of the stope sidewall (instead of being transmitted to the mined-out area below), so that the load completely avoids the recovered area and has stronger stability.

[0048] S9. Conduct tailings cemented filling operation in the stope to form a cemented filling body 9. This step closes the cavity through cemented filling operation and reinforces the overall structure of the stope to provide long-term support. The aim is to cooperate with the retention of the ore body to ensure the durability of the pressure-free arch 8. After the cementing material is consolidated, it forms an overall compressive layer to seal the voids, avoid rock strata movement and enhance safety, and provide radial cementing force at the arch feet of the triangular arched pressure-free structure formed by the retained rock mass to resist its displacement, thereby further strengthening the overall stability.

[0049] This application solves the problem of irregular initial free surface formation through precise positioning and slotting blasting of the cutting well in S1, thus creating geometric conditions for the coordinated blasting of the bottom pillar 1 and the triangular pillar 2, which helps to avoid the problem of blasting energy dispersion caused by boundary loss of control; through the positioning and layout of the bottom pillar drilling tunnel 5 in S2 and the coordinated construction of the upward parallel medium-deep hole 6 in S3, the problem of drilling path deviation of the bottom pillar 1 ore body is solved, thereby optimizing the blasting focusing effect, which helps to improve the recovery efficiency of the bottom pillar 1 ore body and form a compensation space, providing a stable base for the blasting of the triangular pillar 2; through the priority blasting of the bottom pillar 1 ore body in S4, the working space is released and the disturbance accumulation of subsequent operations of the triangular pillar 2 is reduced, which helps to maintain the temporary stability of the stope; through the symmetrical arrangement of the parallel drilling tunnels 4 on both sides of the triangular pillar 2 in S5 and the opposing oblique upward fan in S6 The mirror construction of the deep hole 3 in the shape solves the limitation that rigid drill rods cannot drill curved holes, thereby forcing the ore body to fracture along the preset triangular face to form a geometrically regular arched profile, which is conducive to actively constructing the basic form of the pressure-free arch 8 structure; by retaining the upper part of the ore body of the triangular prism 2 in S7 and selectively blasting the middle and lower parts, the contradiction between recovery rate and stability of the filling area is resolved, and the continuity of the intact rock mass is used to form a self-supporting triangular arch, which is conducive to axially transferring the upper load to the side wall surrounding rock rather than the goaf; by retaining the unblasted triangular prism 2 as the filling body under the pressure-free arch 8 in S8 and supplementing it with tailings cemented filling in S9, the defect of insufficient bearing capacity of artificial filling body when the lower part is completely mined out is solved, and the overall compressive strength is enhanced by the radial constraint of the arch foot and the sealing of the cemented body, which is conducive to achieving the unity of long-term stability of the stope and efficient resource recovery.

[0050] In some implementations, refer to Figure 1 In step S5, the parallel rock drilling tunnel 4 has a width of 2.6 meters and a height of 2.6 meters.

[0051] In some implementations, refer to Figure 1 In step S6, the angle between the deep hole 3 in the sector and the top plate is 42 degrees.

[0052] In some implementations, refer to Figure 1 In step S6, the spacing between the three rows of deep holes in the sector is 1.4 meters, and the distance between the bottom of the holes is 1.5 meters.

[0053] In some implementations, refer to Figure 1In step S2, two parallel bottom pillar drilling tunnels 5 are set up, corresponding to the bottom pillar 1 being divided into two mining areas. The addition of parallel tunnels enables zoned blasting of the bottom pillar 1. Specifically, this divides the single bottom pillar 1 ore body into two independent working areas to optimize blasting focus and ore body fragmentation uniformity. The aim is to reduce the load of a single blast and improve drilling accuracy through zoned control. For example, two bottom pillar drilling tunnels 5 are drilled below the bottom pillar 1. The dimensions of the bottom pillar drilling tunnels 5 are 3.0 meters wide and 3.0 meters high; this size is only an example and not unique. The two bottom pillar drilling tunnels 5 are mirror images of the bottom pillar 1, dividing the base into a left working area and a right working area, also referred to as the first working area and the second working area. During blasting, blasting can be carried out in either the left-to-right or right-to-left order. Furthermore, during blasting, ore extraction can begin immediately after blasting the left working area, followed by blasting of the right working area, or ore extraction can be carried out after both working areas have been blasted.

[0054] In some implementations, refer to Figure 1 In step S2, the dimensions of the bottom pillar rock drilling tunnel 5 are 2.6 meters wide and 2.6 meters high.

[0055] In some implementations, refer to Figure 3 In step S3, the two sections of the bottom pillar 1 are blasted separately. The purpose of this step is to release the blasting energy in stages and control the ground pressure transmission path. When the first section of the bottom pillar 1 is blasted for the first time, the resulting local void can induce the surrounding rock stress to transfer to the unblasted area, reducing the remaining ore body constraint force. The second blast utilizes the already formed free face to optimize the blasting energy transmission efficiency, reduce the explosive consumption per unit, and reduce the disturbance of blasting vibration to the stability of the pressure-free arch 8. For example, in the left working area, a medium-deep hole drilling rig is used to construct upward parallel medium-deep holes 6 with a hole row spacing of 1.4 meters and a spacing of 1.8 meters, and a retreating blast is carried out to empty the ore of the bottom pillar 1 in the left working area. Then, in the same way, the amount of explosive is reduced by 15% to 30% (this is only an example for reference; the actual situation needs to be determined based on the integrity of the rock mass and the spatial relationship of the free face) to empty the ore of the bottom pillar 1 in the right working area, and then a remote-controlled mining car is used for centralized ore extraction.

[0056] This implementation method works in direct synergy with the dual-drilling roadway division of the mining area. The dual-roadway layout provides a physical basis for the step-by-step blasting, while the step-by-step blasting decomposes the large-scale ore body into a small-scale blasting sequence through time control. Together, they solve the technical problem of instability of the pressure-free arch 8 induced by the blasting of the large-scale bottom pillar 1.

[0057] This implementation method works in conjunction with the pressure-free arch 8 retention mechanism: the void created by the first blast causes the stress at the arch foot of the pressure-free arch 8 to redistribute, forming a local pressure relief zone; the second blast is carried out in a pressure-relieved environment, reducing the risk of damage to the pre-reserved ore body of the triangular prism 2 (i.e., the carrier of the pressure-free arch 8) by the shock wave, ensuring that its integrity is sufficient to support the load of the filling body in the upper filled area. Thus, through the temporal separation and spatial guidance of the blast energy release, the dynamic instability of the arch structure caused by the concentrated release of energy in a single blast is avoided, while maintaining the directional transfer of stress from the roof of the goaf to the pressure-free arch 8, ultimately ensuring the safety of the stope before the tailings cemented backfilling operation.

[0058] In some implementations, in step S4, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck extraction.

[0059] In some implementations, in step S7, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck extraction.

[0060] In some implementations, refer to Figure 1 In step S6, a YGZ-90 drilling machine is used to drill the rock and form a sloping fan-shaped medium-deep hole 3.

[0061] In some embodiments, an exemplary process for the combined recycling of the base column of a pressure-free arch triangular prism includes:

[0062] Part One:

[0063] First, cutting risers are constructed in the middle or end of the mining area, while simultaneously supplementing the work with upward parallel medium-deep holes to complete the grooving operation. Then, drilling tunnels are arranged on both sides of each triangular prism, see... Figure 1 The rock drilling tunnels are 2.6m x 2.6m in size. Two rock drilling tunnels are arranged within the base column directly below the triangular prism. (See...) Figure 1 The dimensions of the rock-drilling tunnel are 2.6m × 2.6m.

[0064] Part Two:

[0065] During the mining process, firstly, upward parallel medium-deep holes are constructed in the two lower drilling tunnels, as shown in the figure. Figure 1 The boreholes are spaced 1.4m apart and 1.8m apart, and are constructed using a medium-deep hole drilling rig.

[0066] Part Three:

[0067] Subsequently, a reverse blasting was carried out, and the ore was removed using a remote-controlled loader. The blasted ore was found... Figure 2 Complete the recycling of the bottom column resources in this section.

[0068] Part Four:

[0069] In the rock drilling tunnels on both sides of the upper triangular prism, fan-shaped medium-deep holes are constructed with a row spacing of 1.4m and a hole bottom distance of 1.5m. YGZ-90 equipment is used for rock drilling, and the inclination angle of the blast holes near the top plate is required to be 42°.

[0070] Part Five:

[0071] After drilling, blasting is carried out in a backward manner. The blasting can utilize the lower bottom column void 7 as compensation space. After the triangular column blasting is completed, a remote-controlled loader is used to remove the ore, thus completing the recovery of triangular column resources in this section.

[0072] Part Six:

[0073] After the triangular prism is blasted, a pressure-free arch can be formed under the filling material, see... Figure 3 The arched roof structure has self-stability, which can greatly improve the stability of the upper filling body and the rock roof, and ensure the safety of personnel and equipment operations in the mining area.

[0074] Part Seven:

[0075] After the mining of this section of the stope is completed, tailings cementing and backfilling operations will be carried out in the stope. See Figure 4 The requirement is that the strength reaches 3 MPa or higher after 28 days.

[0076] Part 8:

[0077] Then, the process of steps 1-7 is repeated to carry out the next section mining operation until the overall joint recovery of the triangular pillar and the bottom pillar is completed.

[0078] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

[0079] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A combined recycling process for the base column of a pressure-free arched triangular prism, characterized in that, include: S1. Construct cutting risers in the middle or end of the mining area and supplement upward parallel medium-deep holes for grooving operations; S2. Arrange the bottom column rock drilling tunnel (5) in the bottom column (1) directly below the triangular column (2). S3. Construct an upward parallel medium-deep hole (6) in the bottom pillar rock drilling tunnel (5); S4. Blasting the bottom pillar (1) ore body to extract ore; S5. Parallel rock drilling tunnels (4) are arranged on both sides of the triangular prism (2). S6. In the parallel rock drilling tunnel (4) on both sides of the upper triangular column (2), diagonally upward construction is carried out to form a triangular arch-shaped fan-shaped medium-deep hole (3), and no blasting holes are constructed in the upper part of the ore body of the triangular column (2). S7. Blasting the upper triangular prism (2) to extract ore; S8. The unblasted triangular prism (2) ore body is retained as the filling body under the pressure-free arch (8); S9. Tailings cementing and backfilling operations are carried out in the mining area to form cemented backfill (9).

2. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 1, characterized in that, In step S5, the parallel rock drilling tunnel (4) has a width of 2.6 meters and a height of 2.6 meters.

3. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 2, characterized in that, In step S6, the angle between the deep hole (3) in the sector and the top plate is 42 degrees.

4. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 3, characterized in that, In step S6, the spacing between the deep holes (3) in the fan shape is 1.4 meters and the distance between the bottom of the holes is 1.5 meters.

5. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 1, characterized in that, In step S2, two bottom pillar drilling tunnels (5) are arranged in parallel, and correspondingly, the bottom pillars (1) are divided into two mining areas.

6. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 5, characterized in that, In step S2, the bottom pillar rock drilling tunnel (5) has a width of 2.6 meters and a height of 2.6 meters.

7. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 5, characterized in that, In step S3, the two bottom columns (1) are blasted separately.

8. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 1, characterized in that, In step S4, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck.

9. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 1, characterized in that, In step S7, the blasting method is a backward blasting method, and the ore extraction method is a remote-controlled ore truck.

10. The combined recycling process for the base column of a pressure-free arched triangular prism according to claim 1, characterized in that, In step S6, the YGZ-90 equipment is used to drill the rock and form a sloping fan-shaped medium-deep hole (3).

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