• Explosives and Blasting
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• v.34 no.2
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• pp.1-9
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• 2016

In this study, the field tests were performed on V-cut, PLHBM 1 hole, PLHBM 2 hole in gneiss area in order to compare the effects of the vibration decay of a tunnel cut-hole according to the number of PLHBM holes with scaled distance. Based on the prediction equation of blasting vibration from the result of the tests, the decay rate of vibration were confirmed 21.8~61.1% using PLHBM 1 hole, 35.7~79.3% using PLHBM 2 hole for scaled distance within $10{\sim}100m/kg^{1/2}$ on the basis of V-cut PPV. As the scaled distance was increased, the effect of vibration decay was decreased. The effect of vibration decay of cut-hole for intial PLHBM 1~2 hole was significantly high.

• Explosives and Blasting
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• v.30 no.2
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• pp.66-76
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• 2012

Blasting technology aims to maximize digging efficiency as well as minimize vibration and noise. So, it is key point of blasting technology to raise blasting effect as much as possible and reduce vibration and noise and the design of PLHBM that is the tunnel blasting method having such merit was studied in this paper. PLHBM has the excellent blasting efficiency as it drills the empty hole with high caliber of 250~1,000mm at centre cut, contributes to blasting vibration reduction effect much and can be usefully applied to tunnel blasting sites. So it is judged that it enables the development of tunnel blasting method to be advanced one more step by studying and suggesting the design method of PLHBM.

• Explosives and Blasting
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• v.23 no.1
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• pp.31-39
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• 2005

This study is based on the reseach about conte. track$(Dugso\~wonju)$ double line electric railway tunnel. Authors conducted test blasting to examine the effect of blasting pollution. To be conducted safe and effective work by using this result studies sailable substitution excavation method. No-vibration section generates continuously the vibration of breaker working to go abreast necessarily secondary fragmentation working and according to judging that application is actually difficult in case of the condition of study site, the period of construction, the cost of construction, the efficiency of construction, pre-heavy caliber horizontally boring working + line drilling method + vibration control secondary blasting method excavation working is possible from level within blast vibration standard.