• Explosives and Blasting
• /
• v.21 no.3
• /
• pp.73-80
• /
• 2003

암반발파에 사용하고 있는 전기식 뇌관과 비전기식 연결뇌관 및 번치 커넥터(Bunch connector), 점화구, 에멀젼류 폭약이 지상에서 기폭 될 때 발생하는 소음을 비교 분석하였다. 에멀젼류 폭약의 폭발소음과 화공품의 기폭소음에 대한 추정식을 도출하였다. 에멀젼류 폭약의 폭발 소음 예측은 반대수 자승근 환산식, 번치 커넥터, 전기식 뇌관 및 비전기식 연결뇌관 및 점화구는 전대수식이 적합한 것으로 판단된다. 소음원으로부터 동일한 거리에서의 소음은 점화구, 비전기식 연결뇌관, 전기식 뇌관 및 번치 커넥터 순으로 높았다. 소음원으로부터 약20∼30m거리의 범위에서 번치 커넥터의 기폭소음은 에멀젼류 폭약 0.250kg의 폭발소음보다 약15.6∼20.2dB(A) 낮고, 비전기식 연결뇌관 보다 약13.5∼16.0dB(A) 높고, 전기식 뇌관 보다는 약6.5∼7.5dB(A) 높게 됨을 알 수 있었다. 점화구는 약20m 거리에서 약 7dB(A)이하 이었다. 에멀젼류 폭약의 폭발과 번치 커넥터의 기폭소음에 미치는 주(主)소음원은 에멀젼류 폭약의 약량과 번치 커넥터의 도폭선임을 확인하였다.

• Explosives and Blasting
• /
• v.37 no.1
• /
• pp.24-33
• /
• 2019

Recently, Electronic Detonators have gradually increased their performance for various purposes such as vibration control and improved Fragmentation. This study analyzed the vibration estimation equations of electric and electronic detonator blast by comprehensive analysis of the vibration data collected during electric and electronic detonator blast waves at the comparison sites of urban areas, geology and soil conditions, stone quarries and mines in different areas of Korea from June 2017 to December 2018. It has been confirmed that electronic detonator blast can meet the criteria for allowing vibration even if maximum charge weight per delay is increased by 1.5 times compared to the electric detonator blast.

• Explosives and Blasting
• /
• v.34 no.4
• /
• pp.19-27
• /
• 2016

Much care should be taken when electric caps are used in blast site than when non-electric initiation systems are used. This is because electric caps can cause premature firing or misfires if stray currents of high magnitude flow into the blasting circuit. If the rock has higher electrical conductivity or lower electrical resistivity, such risks will be increased because the rock will provide more passages for the stray currents to flow into the blasting circuit. In this study, several rock samples obtained at a blast site were tested for electrical resistivity to decide whether electric caps could be used or not in the site. The measured electrical resistivity was $39{\sim}47{\Omega}{\cdot}m$ for the rock samples that had a higher content of metal sulfides. Contrary, the resistivity was $15000{\sim}21000{\Omega}{\cdot}m$ for ordinary rocks. Especially, in the case of the rock of electric resistivity of $39{\Omega}{\cdot}m$, only 2-V electric potential enables a stray current to flow through the rock of 1-m length, which can cause the premature firing of a detonator whose initiation current is 0.4 A. This result shows that electric initiation system should not be used in the site because rocks containing much amount of metal sulfides are widely distributed there.

• Explosives and Blasting
• /
• v.29 no.1
• /
• pp.48-52
• /
• 2011

Non-electric detonator has been used in underground excavations because of its strong resistance against electric impacts. However, electric detonator is often used to initiate the non-electric detonator instead of using an exclusive non-electric blasting machine due to economical reason. Spark Trigger is introduced as a solution of unexpected explosive hazard from using an electric detonator as an initiator of non-electric system. Since Spark Trigger System does not need expensive tube and no plastic waste is left, this system is proved to be more economical and eco-friendly initiate system than the standard non-electric initiating system.

• Journal of Industrial Technology
• /
• v.18
• /
• pp.385-397
• /
• 1998

The firing system for the detonators called ordinary blasting caps have almost completely been substituted by safer and more trust worthy systems that can be classified in two groups ; Electric systems, and Non-electric systems. The characteristics of the different initiation devices for both group will be discussed, along with other useful elements for the correct execution of blastings. These detonators are commercialized in several countries under different names such as HiNEL, Nonel, Anodet, Detaline etc. A great advantage is that they do not initiate blasting agents such as slurries and ANFO, allowing bottom priming to be carried out.

• Explosives and Blasting
• /
• v.31 no.1
• /
• pp.64-75
• /
• 2013

This case study deals with an excavation blasting carried out at "Sooseo-Pyeongtek ${\bigcirc}$-${\bigcirc}$ section construction site" in the vicinity of residential area. Originally, the sequential blasting (multi-stage blasting) using electric detonators was planed in this area. However, there was a concern that the sequential blasting method could increase the construction cost by delaying the construction period due to possible complaints from local residents. As an alternative, electronic deck blasting technique was taken in order to meet the ground vibration regulation (0.2cm/s, in apartment area) and to keep the construction schedule. The performance of the electronic deck charge blasting was two times better than the sequential blasting with electric detonators and the level of ground vibration was also within the regulatory value (0.2cm/s). In particular, it was shown that the use of electronic detonater eDevII, which was developed for tunnel, could provide more convenient and electrically safer working condition.