A method of rock drilling and blasting in which slots are formed in one pass

Abstract

The application discloses a rock drilling and blasting method for forming a cutting groove at one time, which comprises the following steps: constructing different-row half-umbrella-shaped and same-row half-fan-shaped blast holes in a slant direction, the angle of the same-row blast holes gradually increases from bottom to top, a rock drilling machine can be fixed at one position to drill all the blast holes; filling the blast holes with explosives, the charge factor is controlled within 65% to 85%, and the length of staggered plugging between adjacent blast holes; setting an initiation sequence, and a cutting groove is formed at one time after initiation. The method is characterized in that the half-umbrella-shaped blast holes and the same-row half-fan-shaped blast holes are arranged, so that the rock drilling machine can drill all the blast holes at one position, the rock drilling machine does not need to be fixed at multiple positions, the rock drilling preparation time is saved, the rock drilling efficiency is greatly improved, and the cutting groove is formed at one time through setting different initiation sequences, so that the circulation process of multiple times of charging, blasting and shovel loading is avoided, and the blasting efficiency and the shovel loading efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of segmented mining drilling and blasting construction, and more specifically, to a drilling and blasting method that can form a cutting groove in one step to provide compensation space for segmented mining blasting. Background Technology

[0002] Because blasting of ore and rock masses causes fragmentation and expansion, to achieve the desired blasting effect, a free surface and sufficient volume of compensation space must be formed before blasting. Before the first formal blasting mining in a segmented open area, a cutting groove of sufficient volume must be constructed to provide blasting compensation space. The traditional method of cutting groove construction involves first constructing a cutting well, then using the cutting well as the compensation space for drilling and blasting, going through multiple cycles of drilling-blasting-muck removal to form the cutting groove. This process is lengthy, involves many procedures, and requires frequent alternation of operations, severely hindering construction efficiency.

[0003] Therefore, researching a cutting groove construction method with a short process and fewer operation cycles, which involves concentrated rock drilling, single blasting to form the cutting groove, and then concentrated muck removal, can significantly improve the efficiency of cutting groove construction. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a rock drilling and blasting method for forming a cutting groove in one step.

[0005] To solve the above problems, the technical solution of the present invention is: a rock drilling and blasting method for forming a cutting groove in one step, the method specifically including the following steps:

[0006] S1) Fix the blast hole drilling rig at the middle position of the end of the drilling tunnel near the cutting level tunnel, and drill blast holes with 5 rows on one side and 10 rows on both sides symmetrically facing upwards.

[0007] S2) Fill the blast hole drilled in S1) with explosives;

[0008] S3) Sort the blast holes after S2) charging, set the detonation sequence, and after detonation, a cutting groove is formed.

[0009] Furthermore, the boreholes in the same row are distributed in a semi-fan shape, while those in different rows are distributed in a semi-umbrella shape, and the borehole diameter is not less than 65mm.

[0010] Furthermore, the semi-fan-shaped distribution specifically involves: first determining the position of the borehole of the longest reference row, and then determining the borehole parameters of the reference row.

[0011] Furthermore, the reference row of blast holes is located at the middle position at the end of the rock drilling tunnel. That is, the plane where the triangle connecting the rock drilling machine point to the upper and lower corners of the far end of the cutting groove is located is the plane where the reference blast hole row is located. There are two planes in total, and the two planes are symmetrical. The reference blast hole rows are numbered 3# and 3'.

[0012] The borehole with the closest distance between its bottom and the free face of the cutting level is designated as borehole No. 1, followed by borehole No. 2. The distance between the bottoms of borehole No. 1 and No. 2 is equal to the distance between the bottom of borehole No. 1 and the free face, which is 1.4 to 1.5 m. Based on this, the angle of borehole No. 1 is determined to be 31°. Subsequently, the angles of other boreholes are gradually increased, and the remaining boreholes are arranged according to a bottom distance of 1.4 to 1.5 m, thereby determining the borehole parameters of the reference row.

[0013] Furthermore, the semi-umbrella-shaped distribution is specifically as follows: the remaining rows have the same borehole angle as rows #3 and #3', the row spacing between different rows is 1.2m to 1.4m, the row spacing between rows #1, #2, and #3 near the end of the upper plate of the cutting groove is 1.2m, the row spacing between rows #3 and #4 is 1.3m, and the row spacing between rows #4 and #5 is 1.4m. Since rows #1 and #1', #2 and #2', #3 and #3', #4 and #4', and #5 and #5' are symmetrical, the row spacing between rows #1', #2', and #3' is 1.2m, the row spacing between rows #3' and #4' is 1.3m, and the row spacing between rows #4' and #5' is 1.4m.

[0014] Furthermore, S2) specifically involves using continuous coupled charging for adjacent boreholes and employing a staggered plugging length method for plugging. The charging coefficient of the boreholes is controlled at 65% to 85%, the charging coefficient of odd-numbered boreholes is controlled at 75% to 85%, and the charging coefficient of even-numbered boreholes is controlled at 65% to 75%.

[0015] Furthermore, the detonation sequence in S3) is as follows: rows 1# and 1', which are closer to the middle of the upper plate, are detonated simultaneously hole by hole. The holes in the same row are detonated from bottom to top. Rows 2# and 2' are detonated one section later than rows 1# and 1'. Rows 3# and 3', 4# and 4', and 5# and 5' are detonated simultaneously hole by hole, one section later than rows 2# and 2'.

[0016] Furthermore, the delay time between adjacent segments is 30 to 50 ms.

[0017] The beneficial effects of this invention are:

[0018] 1. Fixed-point rock drilling. This method, by arranging different rows of half-umbrella-shaped blast holes and half-fan-shaped blast holes in the same row, allows the rock drilling rig to drill all blast holes from a single point. The drilling rig does not need to be moved and fixed multiple times, unlike the traditional method which requires moving the drilling rig once for each row of blast holes. This saves rock drilling preparation time and greatly improves rock drilling efficiency.

[0019] 2. A single blast creates a cutting groove. This method, by setting different detonation sequences and reasonable delay times, creates a cutting groove in a single blast, allowing for concentrated ore extraction after the blast, eliminating the need for multiple cycles of charging, blasting, and shoveling, thus improving blasting and shoveling efficiency. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to more clearly explain the invention and do not constitute an undue limitation of the invention. Obviously, the drawings described below are merely those required for the embodiments; those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings:

[0021] Figure 1 This is a schematic diagram of the overall arrangement of the boreholes in this invention.

[0022] Figure 2 This is a cross-sectional view of the borehole layout of the present invention (including the detonation sequence).

[0023] Figure 3 This is a front view of the present invention.

[0024] In the diagram: 1. Rock drilling tunnel; 2. Blasting hole; 3. Drilling rig center; 4. Cutting level tunnel. Detailed Implementation

[0025] The technical solutions in this embodiment are described in detail below with reference to the accompanying drawings. The embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0026] To make the above-mentioned features, objectives, and advantages of the present invention clearer and easier to understand, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] like Figures 1-3 The rock drilling and blasting method of the present invention, which forms a cutting groove in one step, includes the following steps:

[0028] S1: Construct blast holes in different rows of half-umbrella-shaped and half-fan-shaped sections, with the same section facing upwards. Fix the blast hole drilling rig in the middle position at the end of the drilling tunnel near the cutting level tunnel, and drill blast holes in 5 rows on one side and 10 rows on both sides, with the bottom of the blast holes reaching the boundary of the hanging wall ore body or the section boundary.

[0029] S2: Load explosives into the boreholes. The charging structure is a continuous coupled charge, and adjacent boreholes are plugged with staggered plugging lengths, meaning that the plugging lengths of adjacent boreholes are not exactly the same. The borehole charge coefficient is controlled at 65% to 85% of the borehole depth to avoid excessive concentration of explosives near the borehole opening.

[0030] S3: Set the detonation sequence. The holes in rows 1# and 1', which are closest to the middle of the upper plate, are detonated simultaneously one by one. The holes in the same row are detonated in the order of a, b, c, d, e, f, g. The holes in rows 2# and 2' are detonated one section later than the holes in rows 1# and 1', and are detonated in the order of b, c, d, e, f, g, h. The holes in rows 3# and 3', 4# and 4', and 5# and 5' are detonated simultaneously, one section later than the holes in rows 2# and 2', and are detonated in the order of c, d, e, f, g, h, i.

[0031] Furthermore, in step S1, blast holes are constructed in the same row at a certain bottom distance, and the blast holes in the same row are distributed in a semi-fan shape.

[0032] Furthermore, in step S1, the plane of the triangle connecting the middle position at the end of the rock drilling tunnel, i.e. the position of the rock drilling rig, to the upper and lower corners of the far end of the cutting groove, is the plane where the blast holes of rows 3# and 3' are located. Based on the construction of the blast holes of rows 3# and 3' with the largest blast hole depth, the distance between the first blast hole that is detonated first and the last blast hole that is detonated last and the boundary of the rock mass to be blasted in the cutting groove is controlled to be equivalent to the bottom distance of the hole. Thus, the angles of holes 1 and 7 of rows 3# and 3' are determined. The remaining blast holes in the same row are constructed according to the specified bottom distance of the hole. The angles of the blast holes in other rows are kept consistent with the angles of the blast holes of rows 3# and 3'. All the blast holes in different rows are distributed in a semi-umbrella shape.

[0033] Furthermore, in step S1, a PVC plastic tube is inserted into the blast hole, the inner diameter of the plastic tube is not less than the required blast hole diameter, and the outer wall of the plastic tube is basically in contact with the hole wall.

[0034] Furthermore, in step S2, the blast hole is blown clean with high-pressure air to remove the slag mixed in with the blast hole and keep the blast hole unobstructed and clean.

[0035] Furthermore, in step S2, explosives, digital electronic detonators, and electronic detonator leads are loaded into the borehole using a charging device.

[0036] Furthermore, in step S2, the charge coefficient for odd-numbered boreholes is controlled at 75% to 85%, and the charge coefficient for even-numbered boreholes is controlled at 65% to 75%.

[0037] Furthermore, in step S3, the detonation is initiated in the order of segments a, b, c, d, e, f, g, h, i in parentheses in the figure, with a delay time of 30 to 50 ms between adjacent segments.

[0038] Furthermore, in step S3, the leads of the electronic detonators in each borehole are connected in parallel and bundled together on the main current line, and the detonation is initiated using an electronic detonator.

[0039] Example:

[0040] S1 cutting level 4 is approximately 4m wide and 3.5m high, with a cutting groove height of approximately 10m (including the cutting level 4 height). The blast hole drilling rig is placed and fixed in the middle of the eyebrow line at the end of the drilling rig near the cutting level 4, and drilling of blast holes with a diameter of 65mm begins. The center position of this drilling rig does not need to be changed, and all the required blast holes can be drilled in this position. The drilling rig is spared from multiple relocations and fixations, thus improving drilling efficiency.

[0041] Specifically, the plane at the middle position at the end of the rock drilling tunnel, that is, the plane connecting the upper and lower corners of the triangle from the rock drilling rig point to the far end of the cutting groove, is the plane where the reference blast hole row is located. There are two planes in total, and the two planes are symmetrical, referred to as row 3# and row 3' respectively. First, determine the parameters of the longest rows of blast holes, #3 and #3'. The blast hole with the closest distance between its bottom and the free face of the cutting level is blast hole #1, followed by blast hole #2. The distance between the bottoms of blast holes #1 and #2 is equal to the distance between the bottom of blast hole #1 and the free face, which is 1.4–1.5 m. Based on this, the angle of blast hole #1 is determined to be 31°. Subsequently, the angle of the inclined holes is gradually increased, and all blast holes are arranged with a bottom distance of 1.4–1.5 m. The angle of blast hole #2 is 43°, the angle of blast hole #3 is 52°, the angle of blast hole #4 is 61°, the angle of blast hole #5 is 67°, the angle of blast hole #6 is 75°, and the angle of blast hole #7 is 82°. This determines the angles of rows of blast holes #3 and #3'. The angles of the remaining rows of blast holes are consistent with the angles of this row of blast holes. This method only needs to determine the angle of one row of blast holes to quickly determine the angles of all the remaining rows of blast holes.

[0042] Specifically, the row spacing is 1.2m to 1.4m. The row spacing between rows 1#, 2#, and 3# near the end of the upper plate of the cutting groove is 1.2m, the row spacing between rows 3# and 4# is 1.3m, and the row spacing between rows 4# and 5# is 1.4m. Since rows 1# and 1', 2# and 2', 3# and 3', 4# and 4', and 5# and 5' are symmetrical, the row spacing between rows 1', 2', 3', 4', and 5' is the same as above. The oblique holes of different rows of the cutting groove are distributed in a semi-umbrella shape.

[0043] Specifically, after drilling all the blast holes, PVC pipes are inserted into the blast holes, with the outer wall of the plastic pipe basically fitting against the hole wall to protect the blast holes and prevent them from collapsing.

[0044] The S2 uses a charging device to load explosives, electronic detonators, and lead wires into the boreholes. The charging is continuous and coupled, with a charging coefficient of 85% for borehole 1, 75% for borehole 2, 80% for borehole 3, 75% for borehole 4, 70% for borehole 5, 65% for borehole 6, and 75% for borehole 7. This avoids excessive concentration of explosives at the borehole openings, which could lead to excessive fragmentation during the explosion.

[0045] Specifically, the plugging material used to seal the blast holes is blasting mud, which prevents the explosive gases from being released too quickly, allowing more of their energy to be used to break rocks.

[0046] Specifically, the blast hole is first cleaned with high-pressure air before loading explosives to prevent foreign objects from clogging it.

[0047] S3 uses a sequential blasting method, starting from the bottom and working upwards in the cutting level 4. Rows 1# and 1' are detonated simultaneously, while rows 2# and 2' are detonated one stage later than rows 1# and 1'. Rows 3# and 3', 4# and 4', and 5# and 5' are detonated one stage later than rows 2# and 2'. The earlier rows, closer to the upper boundary of the cutting groove, are detonated first, which provides some compensation space for the later rows, reduces the clamping force of the later rows, and improves the blasting effect.

[0048] Specifically, rows 1# and 1' are detonated in the order of a, b, c, d, e, f, g (in parentheses in the diagram); rows 2# and 2' are detonated in the order of b, c, d, e, f, g, h (in parentheses in the diagram); and rows 3# and 3', 4# and 4', and 5# and 5' are detonated in the order of c, d, e, f, g, h, i (in parentheses in the diagram).

[0049] Specifically, the borehole delay time is 30–50 ms.

[0050] The rock drilling blasting method of the present invention, which forms a cutting groove in one blast, allows the rock drilling rig to drill all the blast holes from a single point by arranging semi-umbrella-shaped blast holes and semi-fan-shaped blast holes in the same row. This eliminates the need to move the drilling rig after each row of blast holes, saving preparation time and significantly improving drilling efficiency. Furthermore, by setting different detonation sequences and reasonable delay times, the cutting groove is formed in one blast, and the ore is extracted in a concentrated time after the blast, eliminating the need for multiple cycles of charging, blasting, and shoveling, thus improving blasting and shoveling efficiency.

[0051] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., 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 this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

Claims

1. A rock blasting method of forming a cutting groove at one time, characterized by, The method specifically includes the following steps: S1) Fix the blast hole drilling rig at the middle position of the end of the drilling tunnel near the cutting level tunnel, and drill blast holes with 5 rows on one side and 10 rows on both sides symmetrically facing upwards. The boreholes are arranged in a semi-fan shape in the same row and in a semi-umbrella shape in different rows, and the borehole diameter is not less than 65mm. The semi-fan-shaped distribution specifically involves: first determining the position of the boreholes in the longest reference row, and then determining the borehole parameters of the reference row; The reference row of blast holes is located at the middle position at the end of the rock drilling tunnel. That is, the plane where the triangle connecting the rock drilling machine point to the upper and lower corners of the far end of the cutting groove is located is the plane where the reference blast hole row is located. There are two planes in total, and the two planes are symmetrical. The reference blast hole rows are numbered 3# and 3'. The borehole with the closest distance between its bottom and the free face of the cutting level is designated as borehole No. 1, followed by borehole No.

2. The distance between the bottoms of borehole No. 1 and No. 2 is equal to the distance between the bottom of borehole No. 1 and the free face, which is 1.4~1.5m. Based on this, the angle of borehole No. 1 is determined to be 31°. Subsequently, the angles of other boreholes are gradually increased, and the remaining boreholes are arranged according to the bottom distance of 1.4~1.5m, thereby determining the borehole parameters of the reference row. S2) Fill the blast hole drilled in S1) with explosives; S3) Sort the blast holes after S2) charging, set the detonation sequence, and after detonation, a cutting groove is formed.

2. The method of claim 1, wherein, The semi-umbrella-shaped distribution is as follows: the remaining rows have the same borehole angle as rows #3 and #3', and the row spacing between different rows is 1.2m to 1.4m. The row spacing between rows #1, #2, and #3, which are close to the end of the upper plate of the cutting groove, is 1.2m, the row spacing between rows #3 and #4 is 1.3m, and the row spacing between rows #4 and #5 is 1.4m. Since rows #1 and #1', #2 and #2', #3 and #3', #4 and #4', and #5 and #5' are symmetrical, the row spacing between rows #1', #2', and #3' is 1.2m, the row spacing between rows #3' and #4' is 1.3m, and the row spacing between rows #4' and #5' is 1.4m.

3. The method of claim 1, wherein, S2) Specifically, adjacent boreholes are continuously coupled with explosive charges and blocked using an alternating blocking length method. The explosive charge coefficient of the borehole is controlled at 65%~85%, the explosive charge coefficient of odd-numbered boreholes is controlled at 75%~85%, and the explosive charge coefficient of even-numbered boreholes is controlled at 65%~75%.

4. The method of claim 2, wherein, The detonation sequence in S3) is as follows: rows 1# and 1', which are close to the middle of the upper plate, are detonated one hole at a time first. The holes in the same row are detonated one hole at a time from bottom to top. Rows 2# and 2' are detonated one section later than rows 1# and 1'. Rows 3# and 3', 4# and 4', and 5# and 5' are detonated one hole at a time, one section later than rows 2# and 2'.

5. The method of claim 4, wherein, The delay time between adjacent segments is 30~50ms.

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