Electronic detonator network arrangement method for preventing blind blasting of blast holes around tunnel

Abstract

The invention discloses an electronic detonator network arrangement method for preventing blind blasting of blast holes around a tunnel. The electronic detonator network arrangement method comprises the following steps that firstly, blasting blast holes are formed in an excavation face of the tunnel, wherein the blasting blast holes comprise slotting blast holes, slot expanding blast holes and peripheral blast holes; 2, in the area, close to the peripheral blast holes, of the bottom, by taking the right side of the tunnel as a starting point, one end of a detonating network branch line is arranged at the starting point, and the other end of the detonating network branch line extends leftwards, extends to the position above the starting point by one circle along the tunnel contour line, continues to extend leftwards till crossing the cut blast hole in the right side and extends upwards again to the cut blast hole in the upper portion; then, the right side of the cut blast hole attached to the left side extends downwards till the cut blast hole at the lowest end is reached; and 3, detonator leg wires in all the slotting blast holes, the slot expanding blast holes and the peripheral blast holes are sequentially connected to the detonating network branch lines corresponding to the detonator leg wires in position. By means of the method, the phenomenon of unexploded shots generated by tunnel blasting peripheral holes is avoided, and the influence of blasting vibration on the surrounding environment is reduced.

Description

Technical Field

[0001] This invention belongs to the field of blasting construction technology, specifically relating to a method for arranging an electronic detonator network to prevent blind blasting of blast holes around tunnels. Background Technology

[0002] In tunnel blasting operations, industrial electronic detonators have completely replaced detonating cord detonators. Detonating cord detonators are used in clusters, where multiple detonating cords extending outside the borehole are bundled together to detonate with a single detonator. Electronic detonators, on the other hand, are used in parallel, with the leads of all electronic detonators extending outside the borehole connected to a single detonation branch. For tunnel blasting operations in complex environments, the amount of explosives detonated with the same delay time must be strictly controlled. This can lead to situations where the delay time of electronic detonators used for detonating peripheral holes in the tunnel blasting design is too long. This can cause flyrock and blasting vibrations from the first detonated hole to affect the detonation of subsequent holes, especially resulting in misfires in peripheral holes, a phenomenon frequently mentioned in domestic literature. Once this occurs, misfire treatment and secondary blasting are required, posing incalculable safety hazards and increasing economic costs and construction time. Summary of the Invention

[0003] The purpose of this invention is to provide a method for arranging an electronic detonator network to prevent blind firing of blast holes around tunnels, thereby avoiding blind firing of holes around tunnel blasting and reducing the impact of blasting vibration on the surrounding environment.

[0004] This invention adopts the following technical solution: a method for arranging an electronic detonator network to prevent misfires in blast holes around tunnels, the method comprising the following steps:

[0005] Step 1: Lay out blasting holes at the tunnel excavation face: Blasting holes include cut-out holes, widening holes, and perimeter holes, among which:

[0006] There are multiple slotting blast holes, located in the middle and lower part of the tunnel excavation face; there are multiple widening blast holes, located on the tunnel excavation face and outside the slotting blast holes.

[0007] There are multiple blast holes around the tunnel, divided into two groups. One group is attached to the tunnel outline and arranged at intervals around the tunnel, while the other group is located in the upper part of the tunnel.

[0008] Step 2: Lay out the detonation network branch line: In the area near the surrounding blast holes at the bottom, starting from the right side of the tunnel, set one end of the detonation network branch line at the starting point and extend the other end to the left, circling around the tunnel outline to the position above the starting point, and continue to extend to the left until it crosses the right-side cut blast hole, then extend upwards again to the upper cut blast hole, and then extend downwards along the right side of the left-side cut blast hole until it reaches the lowest cut blast hole.

[0009] Step 3: Install the first detonator in each slotting blast hole, widening blast hole, and surrounding blast hole, and connect the detonator leads in each slotting blast hole, widening blast hole, and surrounding blast hole to the detonation network branch line corresponding to its position.

[0010] Furthermore, it also includes step four: binding the second detonator to the branch line of the detonation network, and positioning it above the starting point.

[0011] Furthermore, the slotting blast holes are located on the left and right sides of the tunnel's vertical centerline. On the same side, multiple slotting blast holes are arranged in a row from top to bottom at intervals until they approach the bottom of the tunnel. The two rows of slotting blast holes are symmetrical about the tunnel's vertical centerline.

[0012] Furthermore, on the same side, multiple slotting blast holes are arranged in a row at intervals from top to bottom.

[0013] This invention also discloses a blasting method to prevent misfires in blast holes around tunnels. Based on the above-mentioned method for arranging an electronic detonator network to prevent misfires in blast holes around tunnels, the method includes the following steps:

[0014] Step S1: Select one column of slotted blast holes, and use the first detonator in the middle slotted blast hole as the first detonator to initiate detonation. Use the first detonator in the middle slotted blast hole of the other column as the second detonator to initiate detonation. Then, each time, starting from the column where the first detonator is located, and ending at the other column, select the first detonator above and below the first detonator in a loop to determine the detonators to initiate detonation in sequence, and set the detonation delay time in each slotted blast hole.

[0015] Step S2: Select one column of reaming boreholes, with the topmost reaming borehole being the first to detonate. Continue increasing sequentially from top to bottom until the bottommost reaming borehole is the Nth to detonate. Then select another column of reaming boreholes on the other side, increasing sequentially from top to bottom from the (N+1)th to the last reaming borehole at the bottom. Set the detonation delay time for each reaming borehole.

[0016] Step S3: Starting from the bottom of the left or right side, select two holes in sequence along the arrangement of the surrounding blast holes. The first group at the bottom is the first detonation blast hole. Set the detonation delay time for each surrounding blast hole.

[0017] Step S4: After the set delay time, the first detonators in the multiple slotting blast holes are detonated sequentially according to the delay time. When the last slotting blast hole is detonated, the second detonator detonates simultaneously, cutting off the branch line of the detonation network. After the set delay time, the first detonators in the widening blast holes are detonated sequentially according to the delay time, completing the blasting of the widening blast holes. After the set delay time, the first detonators in each group of peripheral blast holes are detonated sequentially according to the delay time, completing the blasting of the peripheral blast holes.

[0018] Furthermore, the first detonator in the enlarged blast hole is delayed after the final detonation delay of the slotted blast hole; the first detonator in the surrounding blast holes is delayed after the final detonation delay of the enlarged blast hole.

[0019] The beneficial effects of this invention are as follows: By adopting the detonation network branch line layout structure of this invention and setting the delay time between blast holes, the blast holes are detonated one by one, which reduces the amount of explosives required for detonation with the same delay time and reduces the impact of blasting vibration on the surrounding environment; the second detonator is tied to the boundary between the detonator leg of the slotted hole and the detonator leg of other blast holes connected by the detonation network branch line, actively severing the detonation network branch line, preventing flying rocks or debris that may be generated after the slotted hole is blasted from pulling the network conductor, and avoiding blind blasting in the surrounding holes of the tunnel blasting. Attached Figure Description

[0020] Figure 1 A schematic diagram of the industrial electronic detonator connection network to prevent blind shots from being fired from surrounding holes;

[0021] Figure 2 Diagram of the gun loading structure for the blast hole;

[0022] Among them: 1. Slotting blast hole, 2. Enlarged blast hole, 3. Peripheral blast hole, 4. Detonation network branch line, 5. Detonator lead wire, 6. First detonator, 7. Blasting blast hole, 8. Explosive charge, 9. Stuffing, 10. Second detonator. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] This invention discloses a method for arranging an electronic detonator network to prevent misfires at blast holes around tunnels, such as... Figure 1 As shown, it includes the following steps:

[0025] Step 1: Deploy blasting holes on the tunnel excavation face. These holes include slotting holes (1), widening holes (2), and peripheral holes (3). Multiple slotting holes (1) are arranged in two rows on the left and right sides of the tunnel's vertical centerline. To achieve better slotting results, they are positioned in the lower middle area of ​​the tunnel excavation face. The distance between adjacent slotting holes (1) is generally set at 40-60 cm. The two rows of slotting holes (1) are symmetrically arranged about the tunnel's vertical centerline. Within the same row, multiple slotting holes (1) are arranged at intervals from top to bottom, with the lowest slotting hole (1) located near the tunnel bottom. The effectiveness of the slotting is evaluated by the hole utilization rate. Using the method described in this invention, the hole utilization rate is approximately 90%.

[0026] There are multiple enlargement blast holes 2, arranged in two rows, located on the left and right sides of the tunnel's vertical centerline, and on the outer side of the corresponding row of cut-out blast holes 1. They are situated in the lower-middle area of ​​the tunnel excavation face, with the side closest to the tunnel outline defined as the outer side. The lowest enlargement blast hole 2 and the lowest cut-out blast hole 1 are on the same horizontal line. Within the same row, the spacing between two adjacent enlargement blast holes 2 is generally 50-80 cm.

[0027] There are multiple peripheral blast holes 3, divided into two groups. One group is attached to the tunnel outline and arranged at intervals around the tunnel. The other group is located in the upper part of the tunnel and arranged in an arc along the tunnel direction. The spacing between two adjacent peripheral blast holes 3 is 40-60 mm. The spacing between two adjacent peripheral blast holes 3 is set according to the surrounding rock grade. The worse the surrounding rock, the larger the spacing.

[0028] For the aforementioned blast holes, the diameter is approximately 40mm when drilled manually, and approximately 50mm when drilled mechanically.

[0029] like Figure 2 The first detonator (6) is located at the bottom of each blasting hole 7 and is connected to the detonator lead wire 5. Multiple explosive charges 8 are set in the blasting hole 7 and facing the opening end of the blasting hole 7. The opening end near the blasting hole 7 is sealed by a plug 9, wherein the detonator lead wire 5 passes through the plug 9.

[0030] Step 2: Deploy the detonation network branch line 4: In the area near the perimeter blast holes 3 at the bottom, starting from the right side of the tunnel, set one end of the detonation network branch line 4 at the starting point, and extend the other end to the left along the tunnel outline, circling around the perimeter blast holes 3 to the position above the starting point; and continue to extend to the left until it crosses the right-side cut-out blast hole 1, then extend upwards again to the upper cut-out blast hole 1, and then extend downwards along the left-side cut-out blast hole 1 until it reaches the lowest cut-out blast hole 1.

[0031] Step 3: Install the first detonator 6 in each of the slotting blast holes 1, the widening blast holes 2, and the surrounding blast holes 3. Connect the detonator leads 5 in each of the slotting blast holes 1, the widening blast holes 2, and the surrounding blast holes 3 to the corresponding detonation network branch line 4. The detonator leads 5 generally extend about 1 meter beyond the blast hole to facilitate connection with the detonation network branch line 4.

[0032] A second detonator 10 with a delay time of 10ms is tied to the detonation network branch line 4, specifically above the starting point. The tying position divides the detonation network branch line 4 into two parts. One part is entirely connected to the first detonator 6 of the detonation slot borehole 1, and the other part is connected to the first detonators 6 of all other boreholes except the detonation slot borehole 1. After the second detonator 10 is detonated, the detonation network branch line 4 connecting the slot borehole 1 and other boreholes is cut off. The purpose of cutting off the detonation network branch line 4 is to prevent the flying rocks generated by the first detonated slot borehole 1 from pulling on the detonation network branch line 4 at this location and pulling on the detonator lead wires 5 of the surrounding boreholes 3 with longer delay times. This also pulls the detonator lead wires 5 of the surrounding boreholes 3 out of the explosive charge in the borehole, preventing the explosives in the surrounding boreholes 3 from being detonated and thus producing a misfire.

[0033] This invention also discloses a blasting method to prevent misfires in blast holes around tunnels. Based on the above-mentioned method for arranging an electronic detonator network to prevent misfires in blast holes around tunnels, the method includes the following steps:

[0034] Step S1: Select one row of slotted holes 1 on the left or right. Use the first detonator 6 in the middle slotted hole 1 as the first detonator to initiate detonation. Set the detonation delay time to 1ms, as industry standards generally do not set the first detonation time of electronic detonators to 0ms, but rather to 1-5ms. Use the first detonator 6 in the middle slotted hole 1 in the other row of slotted holes 1 as the second detonator to initiate detonation. The second detonator is symmetrical to the first detonator. Based on the first detonator, increase the delay time by 1ms, resulting in a delay time of 2ms.

[0035] The first detonator 6 in the slotted blast hole 1 above or below the first detonator is the third detonator. The third detonator is based on the second detonator, and the delay time is increased by 1ms. The fourth detonator is located on the other side and is in the slotted blast hole 1 that is symmetrical to the third detonator.

[0036] If the first detonator 6 in the upper slotted hole 1 adjacent to the first detonator is selected as the third detonator, then the first detonator 6 in the adjacent lower slotted hole 1 will be the fifth detonator. The first detonator 6 in the slotted hole 1 on the other side, symmetrical to the fifth detonator, will be the sixth detonator; and so on, starting from the left slotted hole 1 and ending with the right slotted hole 1 in a symmetrical position, continuously setting them symmetrically left and right. After setting the left and right sides, selection is made in the vertical direction, alternating between up and down. This continues until the delay time of all detonators in the slotted holes 1 is set, with the delay time of the first detonator 6 in two symmetrical slotted holes 1 differing by 1 second.

[0037] Step S2: Select a column of widening boreholes 2, which can be on the left or right. In the selected column, the top widening borehole 2 is the first to detonate, and the number of detonations increases sequentially from top to bottom until the bottom, which is the Nth detonation. Then select a column of widening boreholes 2 on the other side, and the number of detonations increases sequentially from top to bottom, starting from the (N+1)th detonation, until the bottom, which is the last detonation. The first detonation of the widening borehole 2 lags behind the last detonation of the slotting borehole 1 by a delay time of 50ms, and is set to detonate hole by hole with a delay interval of 50ms, ranging from 60ms to 610ms. The first detonation borehole is set to have a delay of 60ms, and from the first detonation to the last detonation, the delay between adjacent boreholes increases by 50ms, i.e., the second detonation borehole is set to have a delay of 110ms.

[0038] Step S3: The first detonator in the peripheral blast hole 3 detonates 50ms after the final detonation delay of the enlarged blast hole 2, and is set according to a 50ms delay interval, ensuring simultaneous detonation of both blast holes. The delay time ranges from 660ms to 1260ms. The purpose of simultaneous detonation of both blast holes is to improve the peripheral blasting effect. Starting from the bottom of either the left or right side, the delay time of the two adjacent peripheral blast holes 3 at the bottom is equal, both being 660ms. Along the arrangement of the peripheral blast holes 3, two are selected sequentially as a group, with the first group at the bottom being the first detonating blast hole. The delay time is increased sequentially from the first detonating blast hole onwards. If the number of peripheral blast holes 3 is odd, it ensures that the bottom of both the left and right sides detonates two blast holes simultaneously.

[0039] Step S4: After the set delay time, the first detonators 6 in the multiple slotting blast holes 1 are detonated sequentially according to the delay time. When the last slotting blast hole 1 is detonated, the second detonator 10 is detonated simultaneously, cutting off the branch line 4 of the detonation network. After the set delay time, the first detonators 6 in the widening blast holes 2 are detonated sequentially according to the delay time, completing the blasting of the widening blast holes 2. After the set delay time, the first detonators 6 in each group of peripheral blast holes 3 are detonated sequentially according to the delay time, completing the blasting of the peripheral blast holes 3.

[0040] All the cut holes 1 were blasted one by one, and the total blasting time was short. When the last cut hole 1 was blasted, the second detonator 10 was detonated at the same time, cutting off the detonation network branch line 4. At this time, the blasted rock fragments in the cut hole 1 had not yet been splashed out. After the detonation network branch line 4 was cut off, the blasted rock fragments flew out. Since the detonation network branch line 4 had been cut off, it was avoided that the flying rocks would pull on the network wires in this part and pull on the detonator leads of the surrounding holes with longer delay times. It would also pull the detonator leads of the surrounding holes out of the explosive charges in the holes, making it impossible to detonate the explosives in the holes and thus producing a misfire.

Claims

1. A method for arranging an electronic detonator network to prevent misfires at blast holes around tunnels, characterized in that, The method includes the following steps: Step 1: Lay out blasting holes at the tunnel excavation face: The blasting holes include slotting holes (1), widening holes (2), and peripheral holes (3), wherein: The slotting blast holes (1) are multiple and are arranged in the middle and lower part of the tunnel excavation face; the widening blast holes (2) are multiple and are arranged on the tunnel excavation face, and are located outside the slotting blast holes (1). The surrounding blast holes (3) are multiple and divided into two groups. One group is attached to the tunnel outline and arranged at intervals around the tunnel, and the other group is located in the upper area of ​​the tunnel. Step 2, Deploy the detonation network branch line (4): In the area near the perimeter blast holes (3) at the bottom, starting from the right side of the tunnel, set one end of the detonation network branch line (4) at the starting point and extend the other end to the left, circling around the tunnel outline to the position above the starting point, and continue to extend to the left until it crosses the right side of the slotting blast hole (1), then extend upward again to the upper slotting blast hole (1), and then extend downward along the right side of the left side of the slotting blast hole (1) until it reaches the bottom slotting blast hole (1). Step 3: First detonators (6) are installed in each of the slotting blast holes (1), widening blast holes (2) and peripheral blast holes (3). The detonator leads (5) in each of the slotting blast holes (1), widening blast holes (2) and peripheral blast holes (3) are connected to the detonation network branch line (4) corresponding to their positions.

2. The method for arranging an electronic detonator network to prevent misfires at blast holes around tunnels as described in claim 1, characterized in that, It also includes step four: binding the second detonator (10) to the branch line (4) of the detonation network and placing it above the starting point.

3. The method for arranging an electronic detonator network to prevent misfires at blast holes around tunnels as described in claim 2, characterized in that, The slotting blast holes (1) are located on the left and right sides of the vertical center line of the tunnel. On the same side, multiple slotting blast holes (1) are arranged in a row from top to bottom until they are close to the bottom of the tunnel. The two rows of slotting blast holes (1) are symmetrical about the vertical center line of the tunnel.

4. The method for arranging an electronic detonator network to prevent misfires at blast holes around tunnels as described in claim 2, characterized in that, On the same side, multiple slotting holes (1) are arranged in a row from top to bottom at intervals.

5. A blasting method to prevent misfires in blast holes around tunnels, based on the electronic detonator network arrangement method for preventing misfires in blast holes around tunnels according to any one of claims 1-3, characterized in that, Includes the following steps: Step S1: Select one column of slotted blast holes (1), and take the first detonator (6) in the middle slotted blast hole (1) as the first detonator to initiate detonation, and take the first detonator (6) in the middle of the other column of slotted blast holes (1) as the second detonator to initiate detonation. Then, each time, take the column where the first detonator to initiate detonation is located as the starting point and the other column as the ending point, and select the first detonator (6) at the top and bottom of the first detonator to initiate detonation in a cycle, determine the detonators to initiate detonation in sequence, and set the detonation delay time in each slotted blast hole (1). Step S2: Select one column of grooving boreholes (2), with the uppermost grooving borehole (2) being the first grooving borehole to be detonated. The grooving boreholes are then increased sequentially from top to bottom until the bottommost grooving borehole is the Nth grooving borehole to be detonated. Then select another column of grooving boreholes (2) on the other side, and the grooving boreholes are increased sequentially from top to bottom until the bottommost grooving borehole is the last grooving borehole to be detonated. Set the detonation delay time for each grooving borehole (2). Step S3: Starting from the bottom of the left or right side, select two in sequence along the arrangement of the surrounding blast holes (3), with the first group at the bottom being the first detonation blast hole, and set the detonation delay time for each of the surrounding blast holes (3). Step S4: After the set delay time, the first detonators (6) in the multiple slotting blast holes (1) are detonated sequentially according to the delay time. When the last slotting blast hole (1) is detonated, the second detonator (10) is detonated simultaneously, cutting off the branch line (4) of the detonation network. After the set delay time, the first detonators (6) in the widening blast holes (2) are detonated sequentially according to the delay time, completing the blasting of the widening blast holes (2). After the set delay time, the first detonators (6) in each group of peripheral blast holes (3) are detonated sequentially according to the delay time, completing the blasting of the peripheral blast holes (3).

6. The blasting method for preventing misfires in blast holes around tunnels as described in claim 5, characterized in that, The first detonator in the enlarged blast hole (2) is delayed by the last detonation delay time of the slotted blast hole (1); the first detonator in the peripheral blast hole (3) is delayed by the last detonation delay time of the enlarged blast hole (2).

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