Interpenetrating tapered triangular straight-hole cut structure and cut blasting method

Abstract

The application discloses a structure of a three-hole triangular straight slotting and a slotting blasting method. The slotting structure comprises three charging holes and three empty holes. The charging holes and the empty holes are straight holes, and the diameter of the empty holes is 1.8-3.6 times of the diameter of the charging holes. On a roadway tunneling working face, the centers of the three charging holes are located at the three vertices of a triangle A respectively, the centers of the three empty holes are located at the three vertices of a triangle B respectively, the triangle A and the triangle B form a mutual embedding structure, that is, only one center of the charging holes is located on one side LB of the triangle B, only one center of the empty holes is located on one side LA of the triangle A, and the side LB is parallel to the side LA. When the slotting blasting is performed, the charging holes are charged and simultaneously initiated, so that the problems of a large number of drilling holes, a low utilization rate of blast holes and a poor blasting effect of the existing slotting method used in a small cross-section roadway can be solved.

Description

Technical Field

[0001] This invention relates to the field of drilling and blasting technology. Specifically, it relates to a triangular straight-hole slotting structure with interlocking diameters and a slotting blasting method. Background Technology

[0002] Small-section tunnels constitute a significant proportion of various mines in my country. When excavating these tunnels, hard rock strata are frequently encountered, characterized by their thickness, high integrity, and strong rock properties. Traditional blasting methods for hard rock strata in small-section tunnels result in low borehole utilization; simply increasing the charge only reduces the size of the blasted rock fragments without improving the overall blasting effect. Therefore, comprehensively optimizing blasting parameters for small-section tunnel excavation under hard rock conditions to achieve maximum benefit with minimal investment is of practical significance for improving the construction progress and overall economic efficiency of small-section tunnels.

[0003] Tunnel excavation experience shows that, given the same number of blast holes and charge, the cut-out method is particularly important. For small-section tunnels, straight-hole cut-out is superior to oblique-hole cut-out, as it is not limited by the tunnel cross-sectional width. Straight-hole cut-out has high blasting efficiency; the more blast holes and the larger their diameter, the better the cut-out effect. However, it also involves higher workload and costs. Therefore, it is necessary to design a cut-out method that requires fewer boreholes and achieves better blasting results for small-section tunnels with thick, highly integral rock strata. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a triangular straight-hole slotting structure with different diameters and a slotting blasting method, so as to solve the problems of large number of drill holes, low utilization rate of blast holes and poor blasting effect when the existing slotting method is used in small cross-section roadways.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] The interlocking triangular straight-hole slotted structure with different diameters includes 3 charging holes and 3 empty holes. Both the charging holes and the empty holes are straight holes, and the diameter of the empty holes is 1.8 to 3.6 times the diameter of the charging holes (within this range, the free surface provided by the empty holes is conducive to the blasting of the charging holes, and the blasting effect is good).

[0007] On the tunnel excavation face: the centers of the three charging holes are located at the three vertices of triangle A; the centers of the three empty holes are located at the three vertices of triangle B; triangle A and triangle B form an interlocking structure, that is: the center of one charging hole is located on one side LB of triangle B, and the center of one empty hole is located on one side LA of triangle A, and LB and LA are parallel.

[0008] In the aforementioned interlocking triangular straight-hole slotting structure with different diameters, on the tunnel excavation face: both triangle A and triangle B are isosceles triangles.

[0009] In the aforementioned interlocking triangular straight-eye slotting structure with different diameters, on the tunnel excavation face: the interlocking structure formed by triangle A and triangle B is rectangular.

[0010] In the above-mentioned interlocking triangular straight-hole slotting structure with different diameters, on the tunnel excavation face: triangle A is an isosceles triangle, and triangle B is an inverted isosceles triangle, that is, the vertex of triangle B is located at the center of the base of triangle A.

[0011] In the aforementioned interlocking triangular straight-hole cut-out structure with different diameters, on the tunnel excavation face: triangle A is an inverted isosceles triangle, and triangle B is a regular isosceles triangle, that is, the vertex angle of triangle A is located at the center of the base of triangle B.

[0012] In the aforementioned interlocking triangular straight-hole slotted structure with varying diameters, the center-to-center distance between the two charging holes located on the waist side of triangle A is 600–750 mm, and the center-to-center distance between the two charging holes located on the base side of triangle A is 600–900 mm; the center-to-center distance between the two empty holes located on the waist side of triangle B is 600–750 mm, and the center-to-center distance between the two empty holes located on the base side of triangle B is 600–900 mm.

[0013] In the above-mentioned interlocking triangular straight-eye slotted structure with different diameters, the depths of the three charging holes are all equal, the depths of the three empty holes are also equal, and the depths of the charging holes and the empty holes are also equal.

[0014] In the aforementioned interlocking triangular straight-hole slotted structure with varying diameters, the diameter of the loading hole is 40–45 mm and the hole depth is 2000–2500 mm; the diameter of the empty hole is 80–150 mm and the hole depth is 2000–2500 mm.

[0015] The method for blasting with interlocking triangular straight-hole slots of varying diameters employs a straight-hole slotting arrangement to form the interlocking triangular straight-hole slot structure as described in claim 1; explosives are loaded into the charging holes and detonated simultaneously.

[0016] In the above-mentioned unequal-diameter interlocking triangular straight-hole blasting method, all three charging holes are equipped with a first-stage detonator, which is located at the bottom of the charging hole; the charging length of the charging hole is 70% of the hole depth; the length of the stemming plug is 500mm; and all detonation is carried out by reverse detonation.

[0017] The technical solution of the present invention achieves the following beneficial technical effects:

[0018] 1. This invention addresses the characteristics of thick and highly integral rock strata in small-section tunnels by designing a non-circular, interlocking triangular straight-hole cut-out structure. In this structure, each charging hole is surrounded by at least two or more empty holes. By controlling the diameter ratio between the empty holes and the charging holes, the diameter of the empty holes is significantly larger than that of the charging holes. Under the hole arrangement of this invention, the charging holes have sufficient free surface during blasting, effectively overcoming the clamping force of hard rock in small-section tunnels. Furthermore, the expansion space of the fractured rock is large, achieving a better blasting effect for small-section tunnel rock strata with a high strength coefficient.

[0019] 2. The interlocking triangular straight-hole cut-out structure of this invention is simple, consisting of only 3 triangular charging holes and 3 large-diameter hollow holes, which interlock to form a rectangle. Only 6 cut-out holes are needed per excavation cycle, making it particularly suitable for small-section roadways. This not only reduces the number of holes drilled but also decreases auxiliary time such as drill relocation, positioning, hole opening, and drill rod replacement, thereby reducing the total time required for arranging blast holes. Furthermore, only 3 of the 6 blast holes are charging holes, reducing the amount of explosives used per unit volume and lowering the cost of explosives and detonators for drill-and-blast excavation. It is suitable for small-section roadways with high strength coefficients (excavation cross-sectional area ≤ 9m²). 2 Construction of ). Attached Figure Description

[0020] Figure 1 Schematic diagram of the interlocking triangular straight-eye slotted structure of embodiment 1 of the present invention;

[0021] Figure 2 Schematic diagram of the interlocking triangular straight-eye slotted structure of different diameters in Embodiment 2 of the present invention.

[0022] The reference numerals in the figure are: 1-charge hole; 2-empty hole. Detailed Implementation

[0023] Example 1

[0024] In this embodiment, a schematic diagram of the interlocking triangular straight-eye slotted structure with different diameters is shown below. Figure 1 It includes three charging holes 1 and three empty holes 2. The charging holes 1 and the empty holes 2 are both straight holes, and the diameter of the empty holes 2 is larger than the diameter of the charging holes 1. The diameter of the charging holes 1 is 42 mm and the depth is 2000 mm. The diameter of the empty holes 2 is 84 mm and the depth is 2000 mm.

[0025] like Figure 1As shown, on the tunnel excavation face: the centers of the three charging holes 1 are located at the three vertices of triangle A; the centers of the three empty holes 2 are located at the three vertices of triangle B; triangle A is an isosceles triangle, and triangle B is an inverted isosceles triangle; triangle A and triangle B form an interlocking structure, and the interlocking structure formed by triangle A and triangle B is a rectangle; that is: the center of one charging hole 1 is located on one side LB of triangle B, and the center of one empty hole 2 is located on one side LA of triangle A, and LB and LA are parallel.

[0026] In this embodiment, on the tunnel excavation face: the center-to-center distance between the two charging holes 1 located on the waist side of triangle A is 600-750mm, and the center-to-center distance between the two charging holes 1 located on the base side of triangle A is 600-900mm; the center-to-center distance between the two empty holes 2 located on the waist side of triangle B is 600-750mm, and the center-to-center distance between the two empty holes 2 located on the base side of triangle B is 600-900mm.

[0027] In this embodiment, the method of blasting with interlocking triangular straight-hole cut-outs of different diameters is as follows: in small cross-section roadways (excavation cross-sectional area of ​​4-9m²), 2 The center of the tunneling face is equipped with the aforementioned interlocking triangular straight-hole slotting structure with varying diameters, arranged by a drilling rig; explosives are loaded into the charging holes 1 and detonated simultaneously. Each of the three charging holes 1 is equipped with a first-stage detonator, which is located at the bottom of the charging hole 1; the length of the explosive charge in each charging hole 1 is 70% of the hole depth; the length of the stemming plug is 500mm; and all detonations are performed using a reverse detonation method.

[0028] Example 2

[0029] The difference between this embodiment and Embodiment 1 lies only in the following: On the tunnel excavation face, triangle A is an inverted isosceles triangle, and triangle B is a regular isosceles triangle, meaning the vertex of triangle A is located at the center of the base of triangle B. Figure 2 .

[0030] The method for blasting interlocking triangular straight-hole slots with different diameters in this embodiment is exactly the same as that in Embodiment 1.

[0031] Compared with the inverted isosceles triangle charging hole arrangement in Example 2, the overall blasting effect of the equilateral isosceles triangle charging hole arrangement in Example 1 is not significantly different. The distance between the bases of the charging holes is the largest, and the blasting conditions are relatively the most unfavorable. Since the rock closer to the tunnel floor experiences greater clamping force, and the base of the equilateral isosceles triangle charging hole arrangement is closer to the tunnel floor than the base of the inverted isosceles triangle charging hole arrangement, under the same blasting conditions, the blasting effect of the inverted isosceles triangle charging hole arrangement will be slightly better than that of the equilateral isosceles triangle charging hole arrangement.

[0032] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A method for blasting interlocking triangular straight-hole slots with different diameters, characterized in that, For small-section roadways with thick rock strata and strong integrity, a triangular straight-hole cut-out structure with different diameters is arranged using a straight-hole cut-out method; after charging the explosive into the charging hole (1), detonation is carried out simultaneously; each of the three charging holes (1) is equipped with a first-stage detonator, which is located at the bottom of the charging hole (1); the length of the explosive in the charging hole (1) is 70% of the hole depth; the length of the stemming mud is 500mm; during detonation, the reverse detonation method is used. The interlocking triangular straight-hole slotted structure with different diameters consists of 3 charging holes (1) and 3 empty holes (2). The charging holes (1) and the empty holes (2) are both straight holes, and the diameter of the empty holes (2) is 1.8 to 3.6 times the diameter of the charging holes (1). On the tunnel excavation face: the centers of the three charging holes (1) are located at the three vertices of triangle A; the centers of the three empty holes (2) are located at the three vertices of triangle B; triangle A and triangle B form an interlocking structure, that is: the center of one charging hole (1) is located on one side LB of triangle B, and the center of one empty hole (2) is located on one side LA of triangle A, and LB is parallel to LA; At the tunnel excavation face: both triangle A and triangle B are isosceles triangles; On the tunnel excavation face: the interlocking structure formed by triangle A and triangle B is rectangular; On the tunnel excavation face: the center-to-center distance between the two charging holes (1) located on the waist side of triangle A is 600-750mm, and the center-to-center distance between the two charging holes (1) located on the base side of triangle A is 600-900mm; the center-to-center distance between the two empty holes (2) located on the waist side of triangle B is 600-750mm, and the center-to-center distance between the two empty holes (2) located on the base side of triangle B is 600-900mm.

2. The blasting method for interlocking triangular straight-hole slotting with different diameters according to claim 1, characterized in that, On the tunnel excavation face: triangle A is an isosceles triangle, and triangle B is an inverted isosceles triangle, that is, the vertex angle of triangle B is located at the center of the base of triangle A.

3. The blasting method for interlocking triangular straight-hole slotting with different diameters according to claim 1, characterized in that, On the tunnel excavation face: triangle A is an inverted isosceles triangle, and triangle B is an upright isosceles triangle, that is, the vertex angle of triangle A is located at the center of the base of triangle B.

4. The blasting method for interlocking triangular straight-hole slotting with different diameters according to any one of claims 1-3, characterized in that, The depths of the three loading holes (1) are all equal, the depths of the three empty holes (2) are also equal, and the depths of the loading holes (1) and the empty holes (2) are also equal.

5. The blasting method for interlocking triangular straight-hole slotting with different diameters according to claim 4, characterized in that, The diameter of the loading hole (1) is 40-45 mm and the depth is 2000-2500 mm; the diameter of the empty hole (2) is 80-150 mm and the depth is 2000-2500 mm.

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