Block crack blasting method for preventing sliding slag in side slope excavation

Abstract

The invention relates to the technical field of civil engineering blasting, and particularly discloses a side slope excavation slag slip prevention block cracking blasting method which comprises the steps that firstly, a plurality of blast holes perpendicular to the ground are drilled in a to-be-excavated area, and a blasting area is formed according to rectangular grid layout; secondly, the blast hole is divided into three sections of charging areas, the first charging section is located at the bottom of the blast hole, the second charging section is located in the middle, and the third charging section is located at the opening of the blast hole; secondly, binding cartridges in blast holes by adopting bamboo chips, connecting the cartridges with detonating cords, arranging electronic detonators at the bottom of the holes, reversely detonating the cartridges, leading out leg wires of the electronic detonators, and connecting to form a detonating network; and finally, connecting the bus with a leg wire of the electronic detonator, setting the delay time of the electronic detonator through the handset, inputting a detonation signal to the electronic detonator through the handset through the bus after confirming blasting alert safety, and then detonating. Blasting energy can act on the rock mass more uniformly, and slag slipping caused by local overlarge impact force is reduced.

Description

Technical Field

[0001] This invention relates to the field of blasting technology in civil engineering, and in particular to a block-fracture blasting method for preventing slag slippage during slope excavation. Background Technology

[0002] When conducting slope blasting excavation in high mountain and canyon terrain, the coupling effect of the propagation characteristics of blasting vibration waves, the dynamic response of the rock mass, and the flyrock ejection effect can easily trigger the sliding, sludge, and rolling of surface rock fragments. Such geological hazards not only damage the original vegetation cover on the slope, causing localized soil erosion and water loss, but may also alter surface runoff paths through the accumulation of debris, thus having a systemic impact on the surrounding ecological environment and soil and water conservation system.

[0003] To address this type of problem, existing technical solutions mainly focus on two dimensions: active control and passive protection. Active intervention measures at the blasting source include reducing the charge per hole using loosening blasting techniques, adjusting the orientation of the free face to optimize rock fragmentation, and employing flexible blasting layers to absorb impact energy. In the slag chute path area, rigid interception systems are constructed using masonry retaining walls, or flexible barrier structures are formed by deploying high-strength protective nets. However, these technical methods generally suffer from limited control effectiveness—active measures cannot completely eliminate the risk of dynamic rock instability, while passive protection structures face problems such as insufficient structural strength or excessive maintenance costs due to the need to cope with the impact of large volumes of gravel. Furthermore, the combined implementation of these measures often leads to a significant increase in construction costs and extended construction periods, and may also disrupt the natural ecological balance due to over-protection. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a new technology for preventing slag sluice box blasting excavation in canyon areas, so as to solve the problem of slag sluice box blasting excavation in canyon areas.

[0005] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes a block-cracking blasting method for preventing slag sliding during slope excavation, which includes: firstly, drilling several blast holes perpendicular to the ground in the area to be excavated, and forming a blasting zone in a rectangular grid layout;

[0006] Secondly, the borehole is divided into three charging sections, with the first charging section located at the bottom of the borehole, the second charging section located in the middle, and the third charging section located at the borehole opening.

[0007] Then: the explosive charge inside the blast hole is tied with bamboo strips and connected with detonating cord. The electronic detonator is placed at the bottom of the hole and the explosive charge is detonated in reverse. The lead wire of the electronic detonator is led out and connected to form a detonation network.

[0008] Finally: Connect the busbar to the electronic detonator lead wire, set the delay time of the electronic detonator through the handheld device, and after confirming that the blasting warning is safe, input the detonation signal to the electronic detonator through the busbar using the handheld device and then detonate.

[0009] In a preferred embodiment of the block-fracturing blasting method for preventing slag sluice in slope excavation according to the present invention: the diameter of the blast hole is 76mm to 90mm, the spacing between adjacent blast holes is 0.8 to 1.0 meters, the blast holes are arranged in groups of four, the four groups of blast holes are arranged in a square array, and adjacent square arrays share a group of blast holes.

[0010] In a preferred embodiment of the block-fracturing blasting method for preventing slag chutes during slope excavation according to the present invention: the first charge section is located at the bottom of the blast hole and its length is one-third of the blast hole depth; the length of the second charge section is one-third.6% of the blast hole depth; and the length of the third charge section is 0.4% of the blast hole depth.

[0011] In a preferred embodiment of the block-cracking blasting method for preventing slag chutes during slope excavation described in this invention: the first charging section employs coupled charging. or The emulsion explosive cartridge is cut open, inserted into the bottom of the hole, and compacted.

[0012] In a preferred embodiment of the block-cracking blasting method for preventing slag chutes during slope excavation described in this invention: the second charge section adopts a decoupled charge and is a smooth blasting charge structure. The emulsion explosive cartridges are filled with intermittent charges, with a linear charge density of 150g / m to 300g / m.

[0013] In a preferred embodiment of the block-cracking blasting method for preventing slag sluices during slope excavation described in this invention: the third section is a blocking section.

[0014] In a preferred embodiment of the block-cracking blasting method for slope excavation and muck dumping described in this invention: Emulsion explosives are tied to the bamboo strips and the detonating cord at intervals. The electronic detonator is placed at the bottom of the hole and detonates in the opposite direction. The leads of the electronic detonator are led out and connected to form a detonation network.

[0015] In a preferred embodiment of the block-cracking blasting method for preventing slag chutes during slope excavation described in this invention: the electronic detonators are divided into three types of unit groups, each type of unit group consisting of the same number of electronic detonator groups, the first unit group and the second unit group having three or four electronic detonator groups, and the third unit group having five electronic detonator groups.

[0016] In a preferred embodiment of the block-cracking blasting method for slope excavation and slag sluice prevention described in this invention: the first unit group and the second unit group respectively correspond to the adjacent boundaries of the blasting zone, and the five electronic detonators of the third unit group are distributed in a symmetrical right-angled pattern in the remaining area of ​​the blasting zone.

[0017] In a preferred embodiment of the block-cracking blasting method for preventing slag sluice in slope excavation according to the present invention: the delay interval between each electronic detonator group adopts a small delay time of 5ms or 10ms, and the electronic detonator groups are detonated in the order from the outside to the inside and from the front to the back.

[0018] The beneficial effects of this invention are as follows: Through a reasonable arrangement of blast holes, grouped in a rectangular grid in a specific manner, the blast holes are evenly distributed, allowing the blasting energy to act more evenly on the rock mass, reducing the amount of debris caused by excessive local impact. The invention employs a three-section charging structure, using different charging methods and explosive types for different charging sections, effectively controlling the blasting power and the degree of rock fragmentation. The coupled charge in the first section ensures the bottom blasting effect; the uncoupled smooth blasting charge structure in the second section ensures uniform rock fragmentation and reduces the generation of large rock fragments; the third section, acting as a blocking section, enhances the blasting effect and reduces rock fragmentation, thus preventing debris flow. The detonation network uses bamboo strips to bind the explosive cartridges and detonating cords, combined with electronic detonators for reverse detonation, improving the reliability and accuracy of detonation. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein:

[0020] Figure 1 A schematic diagram of the borehole layout for the block-fracturing blasting method for preventing slag chutes during slope excavation is shown.

[0021] Figure 2 A schematic diagram of the charge structure for a block-fracturing blasting method for preventing slag chutes during slope excavation is shown.

[0022] Figure 3 A schematic diagram of the detonation network for the block-fracturing blasting method for preventing slag churn during slope excavation is shown. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0024] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0025] Reference Figure 1 This embodiment provides a block-cracking blasting method for preventing slag chutes during slope excavation, including: arranging blast holes: drilling several blast holes perpendicular to the ground in the area to be excavated, forming a blasting zone in a rectangular grid layout; charging: dividing the blast holes into three charging sections, with the first charging section located at the bottom of the hole, the second charging section located in the middle, and the third charging section located at the opening of the hole; connecting the detonation network: binding the explosive cartridges in the blast holes with bamboo strips, connecting them with detonating cords, placing electronic detonators at the bottom of the holes to detonate the explosive charges in the opposite direction, and connecting the leads of the electronic detonators to form a detonation network; delay detonation control: connecting the busbar to the leads of the electronic detonators, setting the delay time of the electronic detonators via a handheld device, and after confirming the safety of the blasting warning, inputting the detonation signal to the electronic detonators via the busbar using the handheld device to initiate the detonation.

[0026] Furthermore, the diameter of the blast holes is 76mm to 90mm, the spacing between adjacent blast holes is 0.8 to 1.0 meters, and the blast holes are arranged in groups of four. The four groups of blast holes are arranged in a square array, and adjacent square arrays share a set of blast holes.

[0027] The spacing between blast holes allows for the rational distribution and transmission of blasting energy within the rock mass. Too small a spacing can lead to excessive concentration of blasting energy, resulting in over-fracture of rock blocks and increasing the risk of debris slippage. Too large a spacing can result in insufficient blasting energy, leading to inadequate rock fragmentation and the formation of large rock blocks. The spacing between blast holes and the arrangement of blast holes in the blasting zone form a rectangular grid blasting zone, which allows the blasting forces of each blast hole to cooperate with each other, ensuring uniform stress on the rock mass and reducing rock block slippage.

[0028] Specifically, the first charge section is located at the bottom of the borehole and its length is one-third of the borehole depth. The second charge section is one-third and six-tenths of the borehole depth, and the third section is one-third and four-tenths of the borehole depth. The first charge section uses a coupled charge. or The emulsion explosive cartridge is cut, inserted into the bottom of the hole, and compacted. The second charge section uses a decoupled charge structure designed for smooth blasting. The emulsion explosive cartridges are filled with explosives at intervals, with a linear charge density of 150g / m to 300g / m, and the third section is the blocking section.

[0029] The segmented charging method allows for different charging methods and explosive types to be used for different charging segments, effectively controlling the blasting power and the degree of rock fragmentation. The coupled charging in the first segment ensures the bottom blasting effect, while the uncoupled smooth blasting charging structure in the second segment ensures uniform rock fragmentation and reduces the generation of large rock fragments. The third segment, acting as a blocking segment, enhances the blasting effect and reduces rock fragment splashing, thereby preventing slag runoff.

[0030] The first charge section is one-third the length of the borehole, ensuring that the blasting energy can fully act on the hard rock mass at the bottom of the hole, providing basic fracturing space for the upper rock mass blasting, and avoiding the risk of overall rock block slippage caused by insufficient fracturing of the bottom rock mass. The second charge section is the longest, in order to form uniform blasting fractures in the rock mass through intermittent charging, so that the rock mass is broken into controllable blocks and avoids the generation of fine debris from crushing. The third charge section is used to seal the borehole, prevent the explosive gas from escaping prematurely, and prolong the time that the blasting energy acts on the rock mass.

[0031] Furthermore, Emulsion explosives are tied to the bamboo strips and the detonating cord at intervals. The electronic detonator is placed at the bottom of the hole and detonates in the opposite direction. The leads of the electronic detonator are connected to form a detonation network. The electronic detonators are divided into three types of unit groups, each consisting of the same number of electronic detonator groups. The first and second unit groups have three or four electronic detonator groups, and the third unit group has five electronic detonator groups. The first and second unit groups correspond to the adjacent boundaries of the blasting zone, respectively. The five electronic detonators of the third unit group are distributed in a symmetrical right-angled pattern in the remaining area of ​​the blasting zone. The delay interval between each electronic detonator group is a small delay time of 5ms or 10ms. The electronic detonator groups are detonated in the order from the outside to the inside and from the front to the back.

[0032] In this method, the electronic detonator is placed at the bottom of the hole and detonates in the opposite direction. The shock wave generated by the explosion propagates from the bottom of the hole towards the opening, ensuring that the first charge section is fully detonated. This avoids energy loss caused by the shock wave and detonation wave colliding in the opposite direction during forward detonation. The reverse detonation can preferentially break the rock mass at the bottom of the hole, forming a blasting sequence from bottom to top. After the bottom rock mass is broken, it provides a buffer space for the upper rock blocks, reducing the kinetic energy of the rock blocks sliding to the outside of the slope. This avoids the rock blocks being directly pushed to the outside of the slope and forming a slag dump due to the hole opening being detonated first.

[0033] Small delay intervals of 5ms and 10ms are used to detonate in batches, allowing energy to be released gradually. At the same time, the detonation is carried out in the order from the outside to the inside and from the front to the back. The electronic detonator group with the shortest delay time is detonated first, located at the outermost corner of the blasting zone, so as to break the rock mass at the edge of the blasting zone first. After the rock blocks of the previous batch have fallen and stabilized, the next batch is detonated. The rock blocks of the previous batch serve as a cushion layer for the rock blocks of the next batch to prevent the subsequent rock blocks from sliding.

[0034] In operation, several blast holes perpendicular to the ground are drilled in the area to be excavated using drilling machinery. The diameter of the blast holes is 90 mm. The spacing between adjacent blast holes is set to 0.8 meters. Four blast holes are grouped together, and the four groups of blast holes are arranged in a square array. Adjacent square arrays share a set of blast holes, so that all blast holes form a blasting zone in a rectangular grid layout.

[0035] Based on the borehole depth, the borehole is divided into three charging sections. Assuming a borehole depth of 6 meters, the first charging section is located at the bottom of the hole, with a length of 2 meters. Coupled charging is used, and [the appropriate charge is selected]. The emulsion explosive cartridge is cut open, inserted into the bottom of the hole, and compacted.

[0036] The second charge section, located in the middle, is 3.2 meters long and uses a decoupled charge structure for smooth blasting. The emulsion explosive cartridges are filled with alternating charges, and the density of the linear charge is controlled at 200g / m.

[0037] The third charge section is located at the orifice and is 0.8 meters long.

[0038] The explosive charge inside the blast hole is tied to bamboo strips and detonating cord. An electronic detonator is placed at the bottom of the hole to initiate the detonation in reverse. The leads of the electronic detonator are led out and connected to form a detonation network.

[0039] Connect the busbar to the electronic detonator, and set the detonation delay time of the electronic detonator through the handheld device. The delay interval between each electronic detonator group is set to a small delay time of 5ms and 10ms respectively. The electronic detonator group at the outermost corner of the blasting zone has the shortest delay time, and then the electronic detonator groups are added sequentially from the outside to the inside and from the front to the back. After confirming that the blasting warning is safe, use the handheld device to input the detonation signal to the electronic detonator through the busbar and then detonate.

[0040] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A block-cracking blasting method for preventing slag chutes during slope excavation, characterized in that: include, First: Drill several blast holes perpendicular to the ground in the area to be excavated, and form a blasting zone in a rectangular grid layout; Secondly, the borehole is divided into three charging sections, with the first charging section located at the bottom of the borehole, the second charging section located in the middle, and the third charging section located at the borehole opening. Then: the explosive charge inside the blast hole is tied with bamboo strips and connected with detonating cord. The electronic detonator is placed at the bottom of the hole and the explosive charge is detonated in reverse. The lead wire of the electronic detonator is led out and connected to form a detonation network. Finally: Connect the busbar to the electronic detonator lead wire, set the delay time of the electronic detonator through the handheld device, and after confirming that the blasting warning is safe, input the detonation signal to the electronic detonator through the busbar using the handheld device and then detonate.

2. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 1, characterized in that: The diameter of the blast hole is 76mm to 90mm, the spacing between adjacent blast holes is 0.8 to 1.0 meters, the blast holes are arranged in groups of four, the four groups of blast holes are arranged in a square array, and adjacent square arrays share a group of blast holes.

3. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 2, characterized in that: The first charge section is located at the bottom of the borehole and has a length of one-third of the borehole depth. The second charge section has a length of one-third and six-tenths of the borehole depth. The third charge section has a length of one-third and four-tenths of the borehole depth.

4. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 3, characterized in that: The first charging section uses coupled charging, where φ70 or φ60 emulsion explosive cartridges are cut, inserted into the bottom of the hole, and compacted.

5. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 4, characterized in that: The second charge section adopts a decoupled charge and a smooth blasting charge structure, with φ32mm emulsion explosive cartridges spaced apart, and a linear charge density of 150g / m to 300g / m.

6. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 5, characterized in that: The third segment is the blockage segment.

7. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 6, characterized in that: The φ32mm emulsion explosive is tied to the bamboo strip and the detonating cord at intervals. The electronic detonator is placed at the bottom of the hole and detonates in the opposite direction. The lead wires of the electronic detonator are led out and connected to form a detonation network.

8. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 7, characterized in that: The electronic detonators are divided into three unit groups, each consisting of the same number of electronic detonator groups. The first and second unit groups have three or four electronic detonator groups, while the third unit group has five electronic detonator groups.

9. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 8, characterized in that: The first unit group and the second unit group respectively correspond to the adjacent boundaries of the blasting zone, and the five electronic detonators of the third unit group are distributed in a symmetrical right-angled pattern in the remaining area of ​​the blasting zone.

10. The block-cracking blasting method for preventing slag chutes during slope excavation according to claim 9, characterized in that: The delay interval between each electronic detonator group is 5ms or 10ms, and the electronic detonator groups are detonated in the order from the outside to the inside and from the front to the back.

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