A novel large-diameter deep hole arrangement structure

Abstract

This utility model discloses a novel large-diameter deep hole arrangement structure. Within a large-diameter deep hole blasting layer, a comb-shaped preparation roadway is arranged, comprising a central roadway and multiple symmetrically arranged chambers. Adjacent chambers are separated by inter-column structures. The width of the central roadway is no greater than the depth of the chamber. Each chamber group forms a blasting area containing three rows of 15 large-diameter deep holes arranged in a straight line. These large-diameter deep holes are divided into 4 inter-column holes, 4 side holes, and 7 central holes based on their location. Each chamber contains 2 inter-column holes and 2 side holes. The amount of explosive charge filling the inter-column holes, central holes, and side holes decreases sequentially. This utility model features a comb-shaped preparation roadway, independently isolated blasting areas, and linearly arranged column holes, side holes, and center holes according to the location. Only 15 blast holes are needed to achieve the blasting effect. It has advantages such as stable preparation roadway, good blasting effect, continuous blasting operation, high safety factor, and 25% saving in mining costs.

Description

Technical Field

[0001] This utility model belongs to the field of underground mining technology, and specifically relates to a novel large-diameter deep-hole arrangement structure suitable for use in large-diameter deep-hole blasting mining methods. Background Technology

[0002] The combined deep-hole and large-diameter deep-hole blasting method is the most commonly used mining method for increasing the depth of mining layers in underground mines. The stope width is typically set at 15m. The upper-level large-diameter deep-hole preparation roadways usually employ a double-row configuration to address the problem of excessively large exposed area in the large-span roadways, and to prevent interference from overly dense or wide arrangement of large-diameter deep holes within the stope width, which could lead to a high proportion of large blocks. The double-row roadway layout generally involves a 2.5m wide pillar and fully connected roadways on one side with a width of 6.0–6.5m. This preparation roadway layout has several problems: First, the pillar left in the middle is prone to collapse due to blasting vibrations during tunneling and blasting, resulting in a large exposed roadway area, insufficient support, and a significantly reduced safety factor. Second, during concentrated blasting of the stope, the lack of surrounding rock buffer at the free face can easily cause a large amount of ore to be overturned into adjacent unblasted areas. This can lead to varying degrees of damage to adjacent unblasted areas, resulting in blockages, collapses, and damage to blast holes in the preparation roadways. This forces personnel and equipment to enter the mining area and work near the goaf, clearing and turning over ore, increasing operational risks, affecting the continuous blasting effect, seriously impacting normal production, and restricting the company's safety and economic benefits. Thirdly, the large number of blast holes is not conducive to cost savings. Taking a single side collapse blast as an example, 20 blast holes need to be laid in a double-row roadway, namely 6 pillar holes, 6 intermediate holes, and 8 side holes, increasing drilling costs and explosive consumption. Utility Model Content

[0003] The purpose of this invention is to propose a novel large-diameter deep hole arrangement structure to solve the problems of high operational risks, large number of blast holes, and high mining costs associated with existing large-diameter deep hole blasting mining that uses double-row roadways as the mining preparation roadway.

[0004] This utility model is achieved through the following technical solution:

[0005] This invention proposes a novel large-diameter deep-hole layout structure. The large-diameter deep-hole blasting involves layered deployment of preparation roadways. These preparation roadways are comb-shaped, comprising a central roadway and multiple sets of chambers symmetrically distributed along both sides of the central roadway. Adjacent chambers are separated by inter-pillars, which are unmined ore bodies. The inter-pillars are positioned closer to the free face as the first inter-pillars and closer to the unblasted area as the second inter-pillars. The width of the central roadway is no greater than the depth of the chambers. Each set of chambers forms a blasting area with a width equal to the stope. Three rows of large-diameter deep holes are arranged within the blasting area, with five such holes arranged in a straight line in each row. The large-diameter deep holes include four inter-pillar holes, four side holes, and seven intermediate holes. The inter-pillar holes are large-diameter deep holes arranged near the first inter-pillar, the side holes are large-diameter deep holes arranged near the boundary of the mining area, and the intermediate holes are the remaining large-diameter deep holes arranged in and around the central roadway. Each chamber is provided with two inter-pillar holes and two side holes, and the amount of explosive charge filling the inter-pillar holes, intermediate holes, and side holes decreases sequentially.

[0006] Based on the above technical solution, by setting up comb-shaped preparation roadways within the layered large-diameter deep-hole blasting, and symmetrically arranging chambers in pairs to form single-blasting zones separated by inter-pillars, each blasting zone is equipped with inter-pillar holes, side holes, and central holes with different charge amounts at different locations. This achieves a superior blasting effect, requiring only 15 large-diameter deep holes to complete a single blast, while also reducing the rate of large ore blocks and ensuring good ore integrity. Furthermore, during the blasting process, the blasting energy is blocked by the surrounding rock formed by the inter-pillars, greatly reducing the amount of ore turned over to unmined areas and preventing damage to the roadways, blast holes, and surrounding rock quality of the next blasting zone. This approach offers advantages such as stable preparation roadways, good single-blasting effect, continuous blasting operations, high operational safety factor, reduced engineering workload, reduced explosive consumption, and low mining costs.

[0007] Preferably, the width of the central roadway within the same blasting area is no more than one-third of the width of the stope, the depth of the chamber is set to 2.2 to 2.3 times the spacing of the large-diameter deep holes, and the thickness of the inter-pillar is set to 1.3 to 1.4 times the spacing of the large-diameter deep holes. This design, by reducing the width of the central roadway and expanding the coverage of the inter-pillar, can minimize ore overturning. At the same time, by limiting the thickness of the inter-pillar, it can prevent the inter-pillar on the free face side from being unable to be effectively mined during blasting, thus avoiding the need for secondary mining and affecting operational safety.

[0008] Preferably, all the large-diameter deep holes adopt a coupled interval charging structure. The length of each large-diameter deep hole is not less than 30m. The length of the charging section and the length of the interval section of each large-diameter deep hole are determined according to the length of the large-diameter deep hole and the preset blasting range. Each charging section is filled with strip-shaped emulsion explosive rolls. Each layer of charging section is separated by a 1.0m interval formed by bamboo tubes, bamboo strips or PVC pipes. Both the opening and bottom of each large-diameter deep hole are provided with sealing sections, which are filled with yellow sand. The purpose of this design is to reasonably control the blasting range of each large-diameter deep hole and save explosives, so as to achieve a better blasting effect and control mining costs.

[0009] Furthermore, the charging structure of the inter-column hole has 14 charging sections. The charging section near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections is filled with 4 emulsion explosive rolls. The length of the yellow sand sealing at the hole opening is not less than 2.34m. This design, by increasing the amount of explosive in the inter-column hole and expanding the superposition of blasting energy of different charging sections, can ensure that the first inter-column near the empty area is fully blasted and forms ore of a suitable size, thus ensuring the blasting effect.

[0010] Furthermore, the charging structure of the intermediate hole has 16 charging sections. The charging section near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections is filled with 4 emulsion explosive rolls. The length of the yellow sand sealing at the hole opening is not less than 2.48m. This design can enable the ore body in the central roadway and the end area of ​​the pillar to be fully blasted and ensure sufficient blasting height.

[0011] Furthermore, the side hole's charging structure has 20 charging sections, each filled with 2 emulsion explosive rolls, and the length of the yellow sand sealing at the hole opening is not less than 1.7m. This design, by reducing the amount of explosive in the side hole, can ensure the formation of a relatively flat stope boundary and will not cause the collapse of the second pillar near the unblasted area, effectively ensuring operational safety.

[0012] Furthermore, the orifice of the large-diameter deep hole is provided with a 5m reserved section. The side of the reserved section closest to the uppermost charge section is filled with 3.0 to 3.5m of yellow sand to form an orifice sealing section. This design, by leaving a certain length of space, can avoid excessive upward propagation of blasting energy, which would cause excessive impact on the top ore body of the blasting layer, resulting in phenomena such as spalling and collapse. This is beneficial to improving the safety of blasting operations without affecting the blasting effect.

[0013] Furthermore, the large-diameter deep hole employs a combined initiation network of electronic digital detonators and detonating cords. The electronic digital detonators are located within the hole-sealing section and are connected to an external initiation device via detonator leads. The detonating cords penetrate all charge sections and protrude 0.5m from the hole-sealing section at the hole opening. The electronic digital detonators are bundled with the detonating cords and used to detonate the detonating cords. The detonating cords are used to detonate the emulsion explosive rolls within each charge section of the large-diameter deep hole.

[0014] Furthermore, within the same blasting area, the central hole is detonated first, followed by the intermediate and side holes. The detonation follows the principle of detonating the center first, alternating between the left and right sides, with each detonation interval set to 25ms. The central hole is the large-diameter deep hole near the free surface, which is the first detonation hole.

[0015] Beneficial effects

[0016] One or more of the above technical solutions have the following beneficial effects:

[0017] To address the shortcomings of existing large-diameter deep-hole blasting mining methods that use double-row roadways as preparation roadways, which are prone to ore overturning and damage to adjacent unblasted areas during blasting, significantly reducing operational safety and increasing blasting difficulty, and require a denser number of blast holes to ensure blasting effectiveness (which is detrimental to cost savings), a comb-shaped preparation roadway is designed within the large-diameter deep-hole blasting layers. The chambers are symmetrically arranged in pairs to form single-blasting zones separated by pillars. Each blasting zone requires only 3 rows of 15 large-diameter deep holes, which can be directly laid out in a straight line (replacing the original...). The recessed, staggered arrangement of boreholes in the same row facilitates drilling positioning. Large-diameter deep holes are divided into pillar holes, side holes, and central holes based on their location, with different charging structures distributed accordingly. This allows for blasting with fewer boreholes and less explosive consumption, achieving better blasting results such as a lower rate of large ore pieces and better ore integrity. Furthermore, the pillars form a surrounding rock barrier in most of the blasting area (i.e., only the width of the central roadway cannot form a barrier), greatly reducing the amount of ore being transferred from the blasting area to unmined areas. This also helps ensure the integrity and accuracy of the roadways, boreholes, and surrounding rock in the next blasting area. By adopting this layout structure, the advantages include stable mining roadways, good single-blasting effect, continuous blasting operations, high operational safety factor, and approximately 25% cost savings in mining. Attached Figure Description

[0018] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0019] Figure 1 This is a plan view of the arrangement structure of this utility model;

[0020] Figure 2 This is a schematic diagram of the charge structure of this utility model. Figure 1 (a) is a pivot hole, (b) is a middle hole, and (c) is a side hole;

[0021] Figure 3 This is a schematic diagram of the charge structure of this utility model. Figure 2 (a) is a pivot hole, (b) is a middle hole, and (c) is a side hole;

[0022] In the diagram: 1. Mining boundary; 2. Preparatory roadway; 21. Central roadway; 22. Chamber; 23. Interstitial pillar; 231. First interstitial pillar; 232. Second interstitial pillar; 3. Blasting area; 4. Large-diameter deep hole; 41. Interstitial pillar hole; 43. Side hole; 42. Middle hole; 5. Charging structure; 51. Hole opening sealing section; 52. Interval section; 53. Charging section; 54. Hole bottom sealing section; 55. Electronic digital detonator; 57. Detonating cord; 56. Detonator lead wire; 58. Reserved section. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.

[0024] This utility model provides a novel large-diameter deep-hole layout structure. A preparation roadway 2 is arranged within the width of a stope in a large-diameter deep-hole blasting stratification. The stope width is set to a standard 15m. The preparation roadway 2 is comb-shaped, including a central roadway 21 and multiple sets of chambers 22 symmetrically distributed on both sides of the central roadway 21. Adjacent chambers 22 are separated by inter-pillars 23, which are unmined ore bodies. The inter-pillars 23 are located closer to the free face and are designated as the second inter-pillars 232 closer to the unblasted area. The width of the central roadway 21 is not large. At the depth of the chambers 22, each group of chambers 22 forms a blasting zone 3 with the same width as the stope. Preferably, the excavation boundary of the chambers 22 is slightly larger than the stope boundary 1, with the excess width set at approximately 1.0 times the blasting radius of the side holes 43. Within the same blasting zone 3, the width of the central roadway 21 is no greater than one-third of the stope width. The depth of the chambers 22 is set at 2.2 to 2.3 times the spacing of the large-diameter deep holes 4, and the thickness of the interstitial pillars 23 is set at 1.3 to 1.4 times the spacing of the large-diameter deep holes 4. Specifically, in this embodiment, as... Figure 1 As shown, the width of chamber 22 (i.e., the vertical direction of the blasting advance direction) is set to 5.5m, the depth (i.e., the length along the blasting advance direction) is set to 6.0m, the width of the central roadway 21 is set to 4.0m, the thickness of the inter-pillar 23 is set to 3.5m, and the depth of the two side chambers 22 extends to the boundary 1 of the mining area.

[0025] Three rows of large-diameter deep holes 4 are arranged within the blasting zone 3, with five large-diameter deep holes 4 arranged in a straight line in each row, i.e., refer to Figure 1Within the blasting zone 3, large-diameter deep holes 4 are arranged in a grid pattern with a row spacing of 2.5m and a hole spacing of 3.5m. The large-diameter deep holes 4 include four inter-pillar holes 41, four side holes 43, and seven intermediate holes 42. The inter-pillar holes 41 are large-diameter deep holes 4 located near the first inter-pillar 231. The side holes 43 are large-diameter deep holes 4 located near the mining boundary 1. The intermediate holes 42 are the remaining large-diameter deep holes 4 located in and around the central roadway 21. Each chamber 22 is provided with two inter-pillar holes 41 and two side holes 43. The amount of explosive charge filling the inter-pillar holes 41, intermediate holes 42, and side holes 43 decreases sequentially.

[0026] The large-diameter deep holes 4 all adopt a coupled interval charging structure 5. The length of the large-diameter deep holes 4 is not less than 30m. The length of the charging section 53 and the length of the interval section 52 of the large-diameter deep holes 4 are determined according to the length of the large-diameter deep holes 4 and the preset blasting range. Each charging section 53 is filled with strip-shaped emulsion explosive rolls. Each layer of charging section 53 is separated by a 1.0m interval through bamboo tubes, bamboo strips, or PVC pipes. The opening of the large-diameter deep holes 4 is provided with an opening sealing section 51 and a bottom sealing section 54. Both the opening sealing section 51 and the bottom sealing section 54 are filled with yellow sand. The bottom sealing section 54 includes cement blocks with a total length of 1.0m, forming a bottom resistance line. The opening sealing section 54 is specifically designed according to the charge amount and the superimposed blasting energy range. Specifically, as shown in the figure... Figure 2 As shown, the length of the borehole of the large-diameter deep hole 4 is set to 34.3m. The charging structure 5 of the inter-column hole 41 has 14 layers of charging sections 53. The charging section 53 near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections 53 is filled with 4 emulsion explosive rolls. The length of the hole opening sealing section 51 is not less than 2.34m. The charging structure 5 of the intermediate hole 42 has 16 layers of charging sections 53. The charging section 53 near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections 53 is filled with 4 emulsion explosive rolls. The length of the hole opening sealing section 51 is not less than 2.48m. The charging structure 5 of the side hole 43 has 20 layers of charging sections 53. Each charging section 53 is filled with 2 emulsion explosive rolls. The length of the hole opening sealing section 51 is not less than 1.7m.

[0027] The large-diameter deep hole 4 employs a combined initiation network and orifice initiation method using electronic digital detonators 55 and detonating cord 57. The electronic digital detonators 55 are located within the orifice sealing section 51 and are connected to an external initiation device (not shown in the attached diagram) via detonator leads 56. The detonating cord 57 penetrates all charge sections 53, with a length of 0.5m protruding from the orifice sealing section 51. The electronic digital detonators 55 are bundled with the detonating cord 57 and used to detonate the detonating cord 57. The detonating cord 57 is used to detonate the emulsion explosive rolls within each charge section 53 of the large-diameter deep hole 4. Specifically, depending on the length of the charge section 53, the intermediate column hole 41 is initiated using a column charge, the intermediate hole 42 using a spherical charge, and the side hole 43 using a short charge and short air column plug.

[0028] Within the same blasting zone 3, the detonation sequence of the large-diameter deep holes 4 is as follows: first detonate the central hole 42, then detonate the intermediate column holes 41 and the side holes 43. Detonation follows a center-first detonation pattern, alternating between left and right holes, with each detonation interval set at 25ms. The central hole 42 is the first large-diameter deep hole 4 located near the free surface. (Refer to...) Figure 1 As shown, the first row of central blast holes near the free face is set as 0ms detonation holes. The left and right blast holes are detonated alternately at 25ms intervals. Then, the second row of central blast holes (75ms interval from the first blast hole) detonates after a 25ms interval, alternating between left and right. The third row of central blast holes (150ms interval from the first blast hole) detonates alternately between left and right, including two inter-column holes 41. Detonations then proceed sequentially along the stope boundary. Each detonation follows the principle of alternating between the middle and the sides, completing the blasting operation of all large-diameter deep holes 4 in one blasting area 3. This detonation sequence helps eliminate energy interaction between adjacent blast holes, avoids excessively fine ore fragmentation and damage to the surrounding unblasted ore body, and effectively improves the blasting effect.

[0029] As an improved implementation method, such as Figure 3 As shown, the charging structure 5 of the large-diameter deep hole 4 optimizes the hole-sealing section 51. Specifically, the hole-sealing section 58 is provided with a 5.0m reserved section 58. The reserved section 58 is filled with 3.0 to 3.5m of yellow sand on the side near the uppermost charging section 53 to form the hole-sealing section 51. A gap length of 1.5 to 2.0m is formed above the hole-sealing section 51, which can effectively avoid excessive upward propagation of blasting energy, which would cause excessive impact on the top ore body of the blasting layer, resulting in phenomena such as spalling and collapse. This is more conducive to improving the safety of blasting operations and improving blasting effect.

[0030] It should be noted that the arrangement structure of this utility model is applicable to areas where an initial free surface has already been formed (i.e., Figure 1The blasting operation following the blasted area shown is not within the scope of this utility model, as the formation process of the initial free face and the arrangement of the blast holes adopt the conventional grooving method.

[0031] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A new large-diameter deep-hole arrangement structure, a large-diameter deep-hole blasting layer is arranged in a mining roadway, characterized in that, The preparation roadway is comb-shaped, including a central roadway and multiple sets of chambers symmetrically distributed on both sides of the central roadway. Adjacent chambers are separated by inter-pillars, which are unmined ore bodies. The inter-pillars are located closer to the free face and closer to the unblasted area. The width of the central roadway is no greater than the depth of the chambers. Each set of chambers forms a blasting area with the same width as the stope. Three rows of large-diameter deep holes are arranged in the blasting area, with five large-diameter deep holes arranged in a straight line in each row. The large-diameter deep holes include four inter-pillar holes, four side holes, and seven intermediate holes. The inter-pillar holes are large-diameter deep holes located near the first inter-pillar, the side holes are large-diameter deep holes located near the stope boundary, and the intermediate holes are the remaining large-diameter deep holes arranged in and around the central roadway. Each chamber has two inter-pillar holes and two side holes. The amount of explosives used to fill the inter-pillar holes, intermediate holes, and side holes decreases sequentially.

2. The novel large-diameter deep hole arrangement structure according to claim 1, characterized in that: Within the same blasting area, the width of the central roadway shall not exceed one-third of the width of the mining area, the depth of the chamber shall be set at 2.2 to 2.3 times the spacing of the large-diameter deep holes, and the thickness of the inter-column shall be set at 1.3 to 1.4 times the spacing of the large-diameter deep holes.

3. The novel large-diameter deep hole arrangement structure according to claim 1, characterized in that: All large-diameter deep holes adopt a coupled interval charging structure. The length of each large-diameter deep hole is not less than 30m. The length of the charging section and the interval section of each large-diameter deep hole are determined according to the length of the large-diameter deep hole and the preset blasting range. Each charging section is filled with strip-shaped emulsion explosive rolls. Each charging section is separated by a 1.0m interval through bamboo tubes, bamboo strips or PVC pipes. Both the opening and bottom of each large-diameter deep hole are provided with sealing sections, which are filled with yellow sand.

4. The novel large-diameter deep hole arrangement structure according to claim 3, characterized in that: The charging structure of the inter-column hole has 14 charging sections. The charging section near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections is filled with 4 emulsion explosive rolls. The length of the yellow sand sealing at the hole opening is not less than 2.34m.

5. The novel large-diameter deep hole arrangement structure according to claim 3, characterized in that: The charging structure of the middle hole has 16 charging sections. The charging section near the hole opening is filled with 5 emulsion explosive rolls, and each of the remaining charging sections is filled with 4 emulsion explosive rolls. The length of the yellow sand sealing at the hole opening is not less than 2.48m.

6. The novel large-diameter deep hole arrangement structure according to claim 3, characterized in that: The side hole's charging structure has 20 charging sections, each filled with 2 emulsion explosive rolls, and the length of the yellow sand sealing at the hole opening is not less than 1.7m.

7. The novel large-diameter deep hole arrangement structure according to claim 3, characterized in that: The large-diameter deep hole has a 5m reserved section at the opening. The reserved section is filled with 3.0 to 3.5m of yellow sand to form a hole sealing section on the side closest to the uppermost charge section.

8. A novel large-diameter deep hole arrangement structure according to claim 3, characterized in that: The large-diameter deep hole employs a combined initiation network of electronic digital detonators and detonating cords. The electronic digital detonators are located within the hole-sealing section and are connected to an external initiation device via detonator leads. The detonating cords penetrate all charge sections and protrude 0.5m from the hole-sealing section at the hole opening. The electronic digital detonators are bundled with the detonating cords and used to detonate them. The detonating cords are used to detonate the emulsion explosive rolls within each charge section of the large-diameter deep hole.

9. A novel large-diameter deep hole arrangement structure according to claim 8, characterized in that: Within the same blasting area, the central hole is detonated first, followed by the intermediate and side holes. The detonation follows the principle of detonating the center first, alternating between the left and right sides. The interval between each detonation is set to 25ms. The central hole is the large-diameter deep hole near the free surface, which is the first detonation hole.

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