A bench deep hole blasting method for open pit mine

Abstract

This invention discloses a deep-hole blasting method for open-pit mine benches, relating to the field of blasting engineering technology. Existing open-pit mine bench blasting methods tend to result in excessive large blocks on the slope and in the front section of the bench, increasing excavation difficulty and transportation safety hazards. This method includes: drilling an inclined first main blast hole and a vertical second main blast hole at the end of the bench near the slope; drilling a first auxiliary hole on the slope that intersects with the first main blast hole; and setting a second auxiliary hole beside the first main blast hole on the bench; loading explosives into each blast hole; connecting all blast holes with detonating wires to form a detonation network; and detonating with a detonator. The first and second main blast holes can be arranged in a quincunx pattern, with the second main blast hole being vertical. Each main blast hole includes a filling section and a loading section. This method compensates for insufficient explosive stress on the slope and in the front section of the bench by setting auxiliary holes, thereby improving the blasting effect.

Description

Technical Field

[0001] This invention relates to the field of blasting engineering technology, and in particular to a deep-hole blasting method for open-pit mine benches. Background Technology

[0002] An open-pit mine bench slope refers to the sloping surface of a bench during the open-pit mine bench mining process. It is a rock slope with a certain angle of inclination, formed during mining operations such as blasting and excavation. This slope connects the bottom of one bench to the top of the next, and is an important component of the open-pit mine's spatial structure. For example, in a large metal open-pit mine, the bench height may be 15 meters, and the bench slope slopes upwards from the bottom of the bench, forming a stable rock slope structure.

[0003] Existing open-pit mine bench blasting methods often reveal an excessive number of large blocks on the slope and in front of the bench after blasting. This excessive presence of large blocks on the slope and in front of the bench (i.e., the part near the slope) makes excavation work (such as electric shovels) more difficult and increases safety hazards during transportation. Summary of the Invention

[0004] The purpose of this invention is to provide a deep-hole blasting method for open-pit mine benches to solve the problems existing in the prior art and improve the blasting effect on the slope and the front section of the bench.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] This invention provides a method for deep-hole blasting of open-pit mine benches, comprising the following steps:

[0007] S1. Drill several rows of inclined first main blast holes on the step to be blasted at one end near the slope, the angle between the first main blast hole and the vertical plane is an inclination angle, and drill second main blast holes on the step to be blasted, and any second main blast hole is farther away from the slope than any first main blast hole.

[0008] S2. Drill several first auxiliary holes on the slope, the first auxiliary holes being arranged in a cross pattern with the first main gun holes; set several second auxiliary holes on the side of the row of first main gun holes closest to the slope on the step.

[0009] S3. Load explosives into all the first main gun ports, the second main gun ports, the first auxiliary ports, and the second auxiliary ports;

[0010] S4. Connect all the first main gun ports, the second main gun ports, the first auxiliary ports and the second auxiliary ports with detonation wires to form a complete detonation network;

[0011] S5. Detonate the entire detonation network using a detonator.

[0012] Preferably, all the first main gun holes and all the second main gun holes are arranged in a quincunx pattern.

[0013] Preferably, the second main gun port is vertically positioned.

[0014] Preferably, the first main gun port includes a first tamping section and a first propellant loading section, and the second main gun port includes a second tamping section and a second propellant loading section.

[0015] Preferably, all the second auxiliary holes are located on the side of the row of first main gun holes closest to the slope that is furthest from the slope.

[0016] Preferably, the bottom end of the first main gun hole is closer to the slope than the top end of the first main gun hole.

[0017] Preferably, the first auxiliary hole is perpendicular to the slope.

[0018] Preferably, the second auxiliary hole is perpendicular to the top surface of the step.

[0019] The present invention achieves the following technical effects compared to the prior art:

[0020] The deep-hole blasting method for open-pit mine benches of the present invention compensates for the insufficient blasting stress on the slope and the front section of the bench by setting a first auxiliary hole on the slope and a second auxiliary hole at the front section of the bench, thereby improving the blasting effect on the slope and the front section of the bench.

[0021] Furthermore, the first auxiliary hole on the slope of the step helps the front row of blast holes overcome the clamping effect of the rock bottom, and is used to solve the problem of large blocks in the front section of the step; the second auxiliary hole in the front section of the step is located between the first main blast hole and the second main blast hole on the step, and is used to solve the problem of large blasting blocks caused by insufficient stress in the upper part of the step.

[0022] Furthermore, by tilting the first main blast hole and positioning its bottom closer to the slope than its top, the minimum resistance line of the step slope can be reduced, allowing the blasting energy to be more concentrated, thereby generating greater destructive power in a smaller area, better utilizing the explosive in the first main blast hole, and improving the blasting effect on the step slope.

[0023] Furthermore, at least two rows of primary blast holes can be set according to actual needs, with the inclination angle of the primary blast holes decreasing as they move further away from the slope. All primary blast holes are arranged at an angle. The purpose of setting at least two rows of primary blast holes is to improve the chassis resistance line and increase its uniformity, ensuring that the chassis resistance line between any adjacent primary blast holes (including the primary and secondary primary blast holes) is relatively small and uniform. A uniform chassis resistance line results in more evenly distributed debris after blasting, reducing the generation of large pieces and flyrock, facilitating subsequent excavation and transportation, and improving operational efficiency. The gradually perpendicular drilling angle, combined with the uniformly distributed resistance line, can reduce uneven damage caused by stress concentration, avoiding localized over-blasting or under-blasting, and ensuring the stability and controllability of the blasting process.

[0024] Furthermore, the cross arrangement of the first auxiliary hole and the first main gun hole can enhance the stress at the bottom angle of the front section of the step, reduce the influence of the clamping effect on the bottom of the rock, and thus improve the rock breaking effect.

[0025] Furthermore, in practical applications, the charging configuration of the first and second auxiliary holes is designed according to the geological and rock mass conditions. Specifically, for hard rock, using auxiliary holes with both detonating charges and filled explosives can increase the blasting energy and improve the rock fragmentation effect. For soft rock, using auxiliary holes with only detonating charges can reduce unnecessary energy consumption, allocate resources more effectively, and thus improve blasting efficiency and economic benefits. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a cross-sectional view of the borehole layout in the deep-hole blasting method for open-pit mine benches according to the present invention.

[0028] Figure 2 This is a diagram showing the arrangement of blast holes on the bench in the deep-hole blasting method for open-pit mine benches according to the present invention.

[0029] In the diagram: 1. Step; 2. Slope; 3. First main gun hole; 301. First tamping section; 302. First charging section; 4. Second main gun hole; 401. Second tamping section; 402. Second charging section; 5. First auxiliary hole; 6. Second auxiliary hole. 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. 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] The purpose of this invention is to provide a deep-hole blasting method for open-pit mine benches to solve the problems existing in the prior art and improve the blasting effect on the slope and the front section of the bench.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] like Figures 1 to 2 As shown, this embodiment provides a deep-hole blasting method for open-pit mine benches, including the following steps:

[0034] S1. Drill a row of first main blast holes 3 on one end of the step 1 to be blasted, near the slope 2, and drill a second main blast hole 4 on the step 1 to be blasted; the first main blast holes 3 are set at an angle.

[0035] S2. Drill several first auxiliary holes 5 on the slope 2. The first auxiliary holes 5 are arranged in a cross pattern with the first main gun hole 3. Set several second auxiliary holes 6 on the side of the step 1 located next to the first main gun hole 3.

[0036] S3. Load explosives into all the first main gun holes 3, the second main gun holes 4, the first auxiliary holes 5 and the second auxiliary holes 6;

[0037] S4. Connect all the first main gun holes 3, the second main gun holes 4, the first auxiliary holes 5 and the second auxiliary holes 6 with detonation wires to form a complete detonation network;

[0038] S5. Detonate the entire detonation network using a detonator.

[0039] Because the stress waves generated after the explosion of the first main blast hole 3 and the second main blast hole 4 will cancel each other out, stress-free zones and stress-reduced zones will be formed at the superposition of stress waves. The explosion of the first auxiliary hole 5 and the second auxiliary hole 6 can effectively compensate for the insufficient stress in the stress-free zones and stress-reduced zones. Specifically, the first auxiliary hole 5 set on the slope 2 helps the front row of blast holes overcome the clamping effect of the rock bottom, so as to solve the problem of large blocks in the front section of step 1. The second auxiliary hole 6 in the front section of step 1 is located between the first main blast hole 3 and the second main blast hole 4 on step 1, so as to solve the problem of large blasting block size caused by insufficient stress in the upper part of step 1.

[0040] In this embodiment, all the first main blast holes 3 and all the second main blast holes 4 are arranged in a quincunx pattern, with the second main blast holes 4 vertically positioned. The first main blast hole 3 includes a first tamping section 301 and a first charge section 302, and the second main blast hole 4 includes a second tamping section 401 and a second charge section 402. All the second auxiliary holes 6 are located on the side of the first main blast hole 3 away from the slope 2. The bottom of the first main blast hole 3 is closer to the slope 2 than the top of the first main blast hole 3. This reduces the minimum resistance line of the slope 2, allowing the blasting energy to be more concentrated, thereby generating greater destructive power in a smaller area, better utilizing the explosive in the first main blast hole 3, and improving the blasting effect of the slope 2 in the step 1. The first auxiliary hole 5 is perpendicular to the slope 2, and the second auxiliary hole 6 is perpendicular to the top surface of the step 1.

[0041] Furthermore, in practical applications, the charging configuration of the first auxiliary hole 5 and the second auxiliary hole 6 needs to be designed according to the geological and rock mass conditions. Specifically, for hard rock, using auxiliary holes with both detonating charges and filled explosives can increase the blasting energy and improve the rock fragmentation effect. For soft rock, using only auxiliary holes with detonating charges can reduce unnecessary energy consumption, allocate resources more effectively, and thus improve blasting efficiency and economic benefits.

[0042] It is worth noting that although only one row of first main gun holes 3 is provided in this embodiment, in actual applications, several rows of first main gun holes 3 can be provided according to actual needs. The angle between the first main gun hole 3 and the vertical plane is an inclination angle, and any second main gun hole 4 is farther away from the slope 2 than any first main gun hole 3. The second auxiliary hole 6 is located on the side of the row of first main gun holes 3 closest to the slope 2 that is farther away from the slope 2. All the first main gun holes 3 in the same row are equidistant from the slope 2, and all the first main gun holes 3 in the same row have the same inclination angle. In any two rows of first main gun holes 3, the inclination angle of the row of first main gun holes 3 closer to the slope 2 is greater than the inclination angle of the other row of first main gun holes 3. In practical applications, technicians should determine the number of rows of the first main blast holes 3 based on a comprehensive consideration of the uniformity of the chassis resistance line distribution and the actual construction complexity. Setting at least two rows of the first main blast holes 3 is intended to improve the chassis resistance line and enhance its uniformity, ensuring that the chassis resistance lines between any adjacent main blast holes (including the first main blast hole 3 and the second main blast hole 4) are relatively small and uniform. A uniform distribution of the chassis resistance line results in more evenly distributed debris after blasting, reducing the generation of large pieces and flyrock, facilitating subsequent excavation and transportation, and improving operational efficiency. Gradually perpendicular drilling angles, combined with a uniformly distributed resistance line, can reduce uneven damage caused by stress concentration, avoiding localized over-blasting or under-blasting, and ensuring the stability and controllability of the blasting process.

[0043] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A bench deep hole blasting method for an open pit mine, characterized by, Includes the following steps: S1. Drill several rows of inclined first main blast holes on the step to be blasted at one end near the slope, the angle between the first main blast hole and the vertical plane is an inclination angle, and drill second main blast holes on the step to be blasted, and any second main blast hole is farther away from the slope than any first main blast hole. The bottom of the first main gun hole is closer to the slope than the top of the first main gun hole; all the first main gun holes in the same row are equidistant from the slope, and all the first main gun holes in the same row have the same inclination angle; in any two rows of first main gun holes, the inclination angle of the row of first main gun holes closer to the slope is greater than the inclination angle of the other row of first main gun holes; all the first main gun holes and all the second main gun holes are arranged in a quincunx pattern; the stress waves generated after the explosion of the first main gun holes and the second main gun holes will have a canceling effect, forming a stress-free zone and a stress-reduced zone; S2. Drill several first auxiliary holes on the slope, the first auxiliary holes being arranged in a cross pattern with the first main gun holes; set several second auxiliary holes on the side of the row of first main gun holes closest to the slope on the step; all second auxiliary holes are located on the side of the row of first main gun holes closest to the slope away from the slope; the first auxiliary holes are perpendicular to the slope; the second auxiliary holes are perpendicular to the top surface of the step; The explosion of the first auxiliary hole and the second auxiliary hole is used to compensate for the stress in the stress-free zone and the stress-reduced zone; S3. Load explosives into all the first main gun ports, the second main gun ports, the first auxiliary ports, and the second auxiliary ports; For hard rock, both the first auxiliary hole and the second auxiliary hole use both detonating charges and filling explosives; For soft rock, the first auxiliary hole and the second auxiliary hole use only detonating charges; S4. Connect all the first main gun ports, the second main gun ports, the first auxiliary ports and the second auxiliary ports with detonation wires to form a complete detonation network; S5. Detonate the entire detonation network using a detonator.

2. The deep-hole blasting method for open-pit mine benches according to claim 1, characterized in that: The second main gun port is set vertically.

3. The deep-hole blasting method for open-pit mine benches according to claim 1, characterized in that: The first main gun port includes a first tamping section and a first propellant loading section, and the second main gun port includes a second tamping section and a second propellant loading section.

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