• Explosives and Blasting
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• v.34 no.3
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• pp.17-20
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• 2016

This paper introduce a multistage parallel non-vibration electronic tunnel blasting cases which adapts Electronic Blasting System(EBS) and the center-cut blasting method to excavating a single line railway tunnel close to residential area. As a result, it was revealed that the vibration and noise showed a reduction of 23.5% and 75% of compared with the allowable standard. We successfully completed the tunnel excavation with decreasing construction time and construction cost and without civil compliant.

• Explosives and Blasting
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• v.16 no.3
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• pp.25-34
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• 1998

This area is covered in Andesite of high compression strength and located in PUSAN SEO-KU. There are many old houses around shaft site. So, we must have a cautious blasting operation. A total of 40 blasts were test at DAE-SHIN Shaft site to study the magnitude and frequency characterization of blast-induced vibration. The effect of viblating frequency on structual damage and site-specific scaling to define th empirical equations were also discussed. The result can be summarized as follows: 1. Some empirical equations were obtained. $V=K\{{\frac{D}{W}}1/3\}^{-n}$ where the values for n and K are estimated to be -1.407 to -2.202 and 643.3489 to 7283.2104 respectively. 2. Dominant frequencies at short distance are in the range of about 75.0 to 91.8 Hz, with some exceptions of about 50Hz, Frequencies observed at long distance are in the range of 10 to 2Hz. It is apparent the shift of dominant frequency down to lower levels at long distance.

• Explosives and Blasting
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• v.20 no.1
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• pp.15-23
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• 2002

1960년대 후반부터 시작된 경제개발계획과 주택정책으로 좁은 국토면적에 많은 주택을 보급하기 위하여 다세대 주택인 고층 아파트가 많이 신축되고 있으며, 고층 건물의 규모 및 그 수가 기하급수적으로 증가함에 따라 인근 건축물과 근접하여 시공하는 경우가 많아지고 있다. 구조물의 신축.증축 및 지하철 공사나 통신선로 등의 지하공간의 활용에 따라 타 공법보다 공사의 진행속도가 빠른 발파작업이 크게 증가하고 있으며, 도심지에서 인근 고층 구조물 및 건축물에 발파작업으로 인한 진동 및 폭음 등의 민원을 일으키는 직접적인 공해가 발생되고 있다. 본 연구지역은 부산 명장동의 "B초등학교 교지정지 및 교사 신축공사" 현장으로서 인근 고층아파트 103동, 104동 및 105동의 1층, 6층, 11층 및 16층에 계측기를 설치하여 발파작업으로 인한 진동 및 폭음이 층별로 미치는 영향을 검토하고자 하였다.검토하고자 하였다.

• Explosives and Blasting
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• v.14 no.3
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• pp.3-9
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• 1996

The scope of this cable works was as follows, it was drilled two shafts, NO. 1 shaft (${\phi}6.8m{\times}31m$), NO.2 shaft (${\phi}6.8m{\times}33m$), ) and it was connected two shaft in Tunneling. The first, it was needed to investigate the surey of influenced of vibration and noise by blastig to near by housing structure. 2nd, it was essential to decide the boundary line of influenced for agriculture water and portable water, by draw down of underground water. Blasting works has been done successfully without any problem, but by draw down of underground water, with in 250m level from #1 shaft, agriculture well drilled 8 place and portable water well drilled 7 place for near by farmers.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.3
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• pp.103-107
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• 2014

To assess a various of workplace noise environment in the tunnel construction site, the measurement is performed while tunnel constructing work. This study focuses on the sound attenuation according to the sound frequency characteristics and the distance from various works in the tunnel. Also, the noise distribution while blasting work is measured according to distance in this study. In addition, the boring processing, muck treatment, and tunnel lining by distance are measured for the noise distributions.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.9
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• pp.928-934
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• 2009

Underwater impulsive sound such as underwater blasting noise, piling noise and stone breaking hammer affects marine animal hearing response and organs. This study describes the characteristics of various impulsive noise from waterfront construction site and their effect on fish. Time constant, peak pressure, energy and SEL(sound exposure level) of four different underwater impulsive sounds are quantified. Auditory and non-auditory tissue damage ranges are derived by comparing their quantities to the exposure criteria for fish. Damage ranges of auditory tissue and non-auditory tissue of underwater boring blast of 150 kg of charge, are about 100 m and 300 m, respectively. Other three impulsive sounds also gives damage effects but less than that of underwater boring blast.

• Explosives and Blasting
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• v.21 no.1
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• pp.49-58
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• 2003

현재 발파의 수행은 채석, 채굴 및 지하철과 도로, 건축, 토목공사 등 다양한 분야에 적용되고 있다. 이에 따라 발파특성의 연구와 관련하여 다양한 이론이 도출되고 있고 사용되지만 발파에 의한 공해인 진동 및 소음의 문제가 대두되면서 또한 이들의 취약점을 보완하기 위해 다양한 공법들이 시행되고 개선되어지고 있다. 본 연구에서는 기존의 발파공법과 Air tubes를 이용한 발파공법을 비교하므로 화약의 사용량을 보다 감소시키고, 기존 전색의 길이를 줄이므로 폭약의 투사면적을 증대시켜 진동 및 폭음을 감소시키고 상대적으로 양호한 파쇄입도를 얻고 상부의 대괴를 최소화하는데 목적이 있다. 따라서 발생하는 진동 및 발파폭음을 크게 감소시킬 수 있으므로 기존 노천발파 및 진동, 소음에 민감한 도심지 발파에서 그 이점을 활용하여 보다 안전적이고 경제적인 발파작업을 수행하는데 연구의 목적이 있다.

• Explosives and Blasting
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• v.21 no.3
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• pp.17-22
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• 2003

발파작업에서 발생하는 공해로 인한 재산상의 피해나 정신적인 피해를 최소화하기 위하여 대부분의 현장에서 제어발파를 시행하고 있다. 이완식 제어발파는 발파의 규모가 일반발파와 비교하여 작고, 대상 구조물이 근거리에 위치하므로 그 전달특성이 다를 수 있다. 근거리에서 계측된 발파진동의 특징은 고주파이고 진동의 지속시간이 짧다. 본 연구는 국내의 8개 지역에서 계측한 자료를 분석하여 이완식 제어발파의 진동전달 특성에 관하여 국내의 현장에서 시공 전에 진동을 추정할 수 있는 진동전파식을 제안하였다. 또한 제어발파시에 사용하는 폐타이어를 부착한 철재매트에 의한 폭풍압의 저감 효과와 전달특성을 분석하였다.

• Tunnel and Underground Space
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• v.25 no.3
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• pp.255-263
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• 2015

Explosive blasting is a very useful tool for mining and civil engineering applications. It, however, may cause severe environmental hazards on adjacent structures due to blasting impact. Blast engineers try to make optimum blast design to provide efficient performance and to minimize the environmental impact as well. It requires a pre-assessment of the impacts resulting from the blasting operation in design stage. One of the common procedures is to evaluate the proposed blast pattern through a series of test blasting in the field. Another approach is to evaluate the possible environmental effects using the numerical methods. There are a number of input parameters to be prepared for the numerical analysis. Some of them are well understood, while some are not. This paper presents some results of sensitivity analysis of the basic input parameters in numerical modelling of blasting problems so as to provide sound understanding of the parameters and some guidelines for input preparation.

• Explosives and Blasting
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• v.32 no.2
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• pp.25-30
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• 2014

Although the construction noise and vibration are transient and intermittent, their impact on the surrounding environment is huge. Since the construction equipment noise and vibration is usually transmitted because of the long distance, the sound insulation and the proper design of anti-vibration measures are very difficult. The regulation requires that the noise and vibration caused by the construction equipments should be measured within 30m from the source, whereas the blasting noise and vibration should be measured at least 60m and 160m away from the source, respectively. Instead of the 2D modelling mainly conducted so far, the 3D analysis of noise and vibration with the consideration of the height and size of the building, mountains and hills in the vicinity of the source is necessary.