• Tunnel and Underground Space
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• v.24 no.2
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• pp.131-142
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• 2014

This study is using electronic-delay system detonator which can input an accurate detonating delay, compare predicted blasting vibration level derived from vibration 3D modelling with real measured blasting vibrations, and then considered modelling results are able to apply blast design. It confirmed there are certain relations between modelling and real vibration data, so modelling prediction method also can be apply design various blast conditions and prediction equation of blast vibration.

• Explosives and Blasting
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• v.28 no.2
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• pp.37-49
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• 2010

Ground vibration caused by blasting in the urban area close to structures can give some indirect damage to human body and may lead to structural damage to buildings. At the stage of design or when complaints were filed by residents, the test blasting in borehole, which is most practical for expressing simple vibration wave form quantitatively, is usually chosen for assessing the degree of damage to structures. In this paper, some lessons gained from the application of electronic detonator triggering system in borehole test blasting are presented. The difference in delay time of detonator when borehole is blasted by electronic detonator and electric detonator are discussed. The peak particle velocities measured at the structure embedded in the similar rock layer to main line of tunnel at test site and measured at the road surface just above the tunnel having different overburden layers were analysed to draw their relationship. By comparing the results with those appearing in some published literatures, the usefulness of the borehole test blasting and the importance of delay time of detonator are addressed.

• Explosives and Blasting
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• v.31 no.1
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• pp.76-86
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• 2013

In order to control tunnel blast vibration for adjacent facilities using electronic detonator, Understanding about the characteristics of near-field ground vibration is necessary. The purpose of this paper is to analyze effects of Cut-area and Extension-area vibration in relation to decision of tunnel blast vibration. These data were obtained at the top monitoring positions while ${\bigcirc}{\bigcirc}{\bigcirc}$ tunnel site of "Wonju~Gangneung double railroad section ${\bigcirc}{\bigcirc}$ construction" was passing under the existing road. Thus, tunnel blasting was conducted by tunnel electronic blasting system with 0.01% high delay-time accuracy. It can be possible that not only keeping maximum charge per delay-time but also preventing amplification of vibration which is occurred by delay-time scatter using common detonators. Additionally, V-Cut was changed into Burn-Cut. The results was presented that vibration level of extension-holes were higher than Cut-holes. Therefore, near-field ground vibration can be effectively minimized using electronic detonators in the Cut area. And also more effective way to reduce tunnel blast vibration is full-face blast using electronic detonators.

• Explosives and Blasting
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• v.22 no.1
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• pp.23-32
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• 2004

터널 발파를 원활히 수행하기 위해서는 암반조건에 적합한 합리적인 설계와 정밀한 천공, 정확한 기폭초시가 기본요소로서 이는 현재 국내 터널 설계.시공 기술 및 기자재의 발달로 만족할 만한 성과를 얻을 수 있다. 특히. 터널발파에서 정확한 기폭초시 부여는 굴진율 및 버럭 파쇄율, 굴착예정선 미려도, 잔여 암반 손상도 등의 시공성에서 뿐만 아니라 소음 및 진동 발생율을 좌우하는 환경적인 측면에서 매우 중요한 요소이다. 기폭요소는 최초 도화선을 활용한 공업뇌관에서 전기뇌관, 비전기식뇌관의 순으로 기폭안전성과 정밀성 면에서 눈부신 성장을 이룩하여 왔으며 특히, 90년대 초에 개발되어 전 세계적으로 최근까지 지속적으로 사용량이 급증하고 있는 전자뇌관은 기폭방식에 일대혁신을 이루었다. 전자기폭 시스템은 기존뇌관의 초시를 결정하는 화약성분의 지연요소 대신에 IC board(전자회로)에 의한 Digital timer로 신호를 발생하여 초시를 결정하는 방식이다. 본 논문에서는 국내 최초로 전자기폭시스템을 활용하여 2003년 9원 23일에서 동년 11월 2일까지 강원도 양구 지역의 $\bigcirc\bigcirc$터널에 전자뇌관을 이용한 시험발파를 실시하였고, 발파에 의한 진동 등을 조사하여 그 효율성을 검토하였다. 이를 위해 전자뇌관의 특성과 장점을 최대한 샅리기 위하여 각공을 발파하는 방식, 즉 1지발에 1공을 발파하는 방식을 채택하고 일반 뇌관과 전자뇌관으로 설계를 하여 각각의 발파효율을 비교하여 보았다. 그 결과 발파진동의 경우 기존뇌관을 이용하여 1공씩을 1지발로 발파를 한 경우에는 18~56%의 진동저감 효과가 있었고. 본선 설계에 의해 진행된 발파에 비하여는 최대 70% 이상의 진동저감 효과가 있는 것으로 나타났다.