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Deep hole liquid carbon dioxide cold explosion method

The invention relates to the technical field of rock breaking, and provides a deep hole liquid carbon dioxide cold blasting method which comprises the following specific steps: (1) designing and calculating drilling and blasting parameters, wherein the parameters comprise aperture, pitch, number of holes, warning distance and quality of used liquid carbon dioxide; (2) determining a …

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Application of Long-Distance Drilling and Blasting Technology to …

By comparing the micro seismic activity cloud maps of the three stages of long-distance drilling blasting and roof deep hole blasting before and after the implementation of long-distance drilling blasting, it can be seen that in the initial roof deep hole blasting stage, the micro seismic activity index in front of the mining area reached 0.5.

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Theory and numerical simulation of deep hole cut blasting based …

For deep hole blasting, the original oblique hole cutting method necessitates the explosive to be concentrated at the bottom of the blast hole, making the distribution of the explosive energy unreasonable. ... The distance between the center hole and the face ZY is 250 mm, the length of the charge is 1.21875 m, and the length of the plug is 1. ...

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03 Saftey in Excavation & Blasting.ppt an | PPT

Simple Sloping • Type B - 1:1 450 • Type C - 1½ :1 340 Note :Greater than 20 feet deep shall be designed by ... equipment within 50 feet of loaded holes. Safety Code For Blasting And Related Drilling Operations 57. • Load only those holes intended to be fired in the next round. • Warning signs posted. • Check all holes for depth ...

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JAn 203 1 of 21 Surface Blasting Safety Procedures

• The minimum distance for personnel is 500 feet. • Safe distances will be determined based on conditions for each blast by the Blasting Foreman or designee. Blasting …

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1910.109

Warning required. Before a blast is fired, the employer shall require that a loud warning signal be given by the person in charge, who has made certain that all surplus explosives are in a safe …

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30 CFR Part 56 -- Safety and Health Standards—Surface Metal …

In determining the blast area, the following factors shall be considered: (1) Geology or material to be blasted. (2) Blast pattern. (3) Burden, depth, diameter, and angle of the holes. (4) Blasting …

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Study on parameter optimization of deep hole cumulative blasting …

Extraction hole #1 was in the effective range of influence being 7 m away from the blasting hole, while extraction hole #5 was not, it being 8 m away from the blasting hole.

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Safe Distance between the Deep-Hole Blasting and the Grouting …

And the safety criterion of the PPV of the grouting curtain was 4.84 cm/s. On the in-situ blasting vibration monitoring data, the Sadov's empirical formula was established, and the safe distance between the deep-hole blasting position and the grouting curtain under different maximum single-hole charges was obtained.

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How to Conduct Blasting Operations Safely? [PDF]

Safety Precautions while Blasting. For the safety of workers, red flags shall be prominently displayed around the area where blasting operations are to be …

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Part 14

means a remnant of a blast hole that did not properly break when the blast was initiated, also referred to as socket; « culot de mine » ... Warning signs (1) A blasting area shall be clearly identified by signs to prevent inadvertent access of vehicles, equipment or pedestrians. ... Quantity-Distance Table for Blasting Explosives Hazard ...

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CMR-2017 NOTES ON EXPLOSIVE AND …

Deep-hole blasting. – ... the shot-firer shall charge or fire a shot only after sufficient warning is given over the area within a radius of 500 meters from the place of firing ... The distance between the 1st row of holes and …

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How to Conduct Blasting Operations Safely? [PDF]

Safety Precautions while Blasting. For the safety of workers, red flags shall be prominently displayed around the area where blasting operations are to be carried out. All the workers at the site shall withdraw to a safe distance of at least 200 meters from the blasting site. An audio warning by blowing whistle shall be given before igniting ...

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1926.905

Powerlines and portable electric cables for equipment being used shall be kept a safe distance from explosives or blasting agents being loaded into drill holes. Cables in the proximity of the blast area shall be deenergized and locked out by the blaster.

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Study on the technology of permeability enhancement of deep hole …

To investigate the impact of deep-hole pre-splitting blasting on gas extraction flow rate, we constructed one blasting hole and four exploratory holes at distances of 2 m, 2.5 m, 3.0 m, and 3.5 m from the blasting hole in the bottom pumping lane …

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Characteristics and Energy Distribution of Blast-Induced Ground

This study proposes an incremental extreme extraction method based on the waveform characteristics of ground vibration signals obtained from open-pit mines to investigate the distribution and characteristics of ground vibration from deep-hole blasting. Firstly, an incremental extreme extraction method is proposed based on the waveform characteristics of …

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Construction Blasting Fundamentals

From a safety perspective, it is important to know how sensitive an explosive is to impact, friction, and heat. ... stringent blast effect control measures, and effective blast area security and warning methods must be evaluated for close-in blasting. ... Large blast holes may be as large as 9 inches or 225 mm. in diameter, while small holes ...

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Key Blasting Parameters for Deep‐Hole Excavation in an …

In the four-hole blasting scheme, the average unit explosive consumption is 1.809 kg/m 3, the average footage of single cycle excavation is about 3.4 m, and the utilization rate of blast holes is up to 92%. From the scenes two empty hole and four empty hole blasting effect data, without changing the total charge and the number of blast holes ...

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Assessing and controlling of boulder deep-hole blasting …

holes are used, the maximum particle velocity of the shaft structure under the inuence of blasting stress wave is 1.47 cm/s, which is within the reasonable safety range. Keywords Metro construction · Boulder · Deep-hole blasting · Vibration response · Vibration reduction measures · Damping hole 1 Introduction

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Crack Extension Characteristics of Deep Hole Pre-splitting Blasting

In underground coal mines, deep-hole pre-splitting blasting (DHPB) is an effective means of attenuating or even eliminating the risk of rockburst induced by the breakage of hard-thick roof. The in-situ stress field and drill geometry are the controlling factors for the performance of DHPB, but their impacts on the rock blasting crack extension characteristics are still not fully …

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Rock-Breaking Mechanism and Application of Combined Long …

In order to address the issue of limited excavation footage in the drilling and blasting of a water diversion tunnel with a cross-section of approximately 10 m2, which is unable to meet the demands of rapid construction, a blasting method combining long and short straight-hole cutting was proposed based on the theories of elastic mechanics, blasting craters, …

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29 CFR 1926.905 -- Loading of explosives or blasting agents.

(j) Powerlines and portable electric cables for equipment being used shall be kept a safe distance from explosives or blasting agents being loaded into drill holes. Cables in the proximity of the …

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Experiment Study of Stemming Length and Stemming Material …

Stemming length and stemming materials are crucial factors in blasting design, which affect the sustainability of mining. This study investigates the influence of stemming length and stemming material on rock fragmentation, stemming recoil, and surface strain response through 15 small-scale model blasting tests. The results indicate that when using clay as a …

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Blasting Safety in Daily Mining Operations

Personnel should be trained in blasting safety, wear appropriate personal protective equipment, follow established procedures and safe work practices, be in communication with the blast operator, and be informed of the …

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Theoretical and numerical simulation investigation of deep hole

Drilling and blasting methods have been used as a common driving technique for shallow-hole driving and blasting in rock roadways. With the advent of digital electronic detonators and the need for increased production efficiency, the traditional blasting design is no longer suitable for deep hole blasting. In this paper, a disperse charge cut blasting method was …

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Long hole charging and blasting

the final swelling void before the full production blasting is started, all these opening methods are followed by initial long-hole production blasting of the closest surrounding holes to enlarge this void. As a general rule, good practice in drilling and charging will include: • Reamed holes, charged and uncharged. • High precision drilling.

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Numerical analysis of deep hole multi-stage cut blasting of vertical

Due to the high in situ stress of the deep rock mass and the restraining effect of the surrounding rock, the deep hole blasting of vertical shaft faces the problems of low borehole utilization rate and poor blasting effect. In this regard, this paper proposes a deep hole multi-stage cut blasting technology of vertical shaft. Preliminary engineering practice shows that such cut …

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Mechanism of Hard-Roof Rock Burst Control by the Deep-Hole Blasting

In underground coal mines, the deep-hole blasting (DHB) technology is generally adopted for thick hard-roof control. This technology uses the energy released by explosives to weaken the energy ...

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Hard Rock Deep Hole Cutting Blasting Technology in Vertical …

The results show that using large diameter empty hole blasting technology in vertical shaft construction of frozen hard rock section can significantly improve the speed of vertical shaft ...

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(PDF) The Effect of Blast-Hole Arrangement, Delay Time, and …

The Effect of Blast-Hole Arrangement, Delay Time, and Decoupling Charge on Rock Damage and Vibration Attenuation in Multihole Blasting January 2022 Shock and Vibration 2022(8):1-18

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