• Explosives and Blasting
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• v.31 no.2
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• pp.50-58
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• 2013

Since various types of safety facilities have been located around blasting construction site, each of the institutions with regard to blast works has prepared limit criterion of blast vibration, respectively. But these criterions applied for limiting vibration are causing harmful effect including construction cost increasement and construction time extension due to exceedable high level application. In this study, more reasonable limit of blast vibration was suggested after reviewing criterions based on existing design and construction cases and analyzing of problems of applied criterions.

• Geomechanics and Engineering
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• v.15 no.6
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• pp.1227-1236
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• 2018

From all of the environmental problems, blast-induced vibrations often cause concern to surrounding residents. It is often claimed that damage to building superstructures is due to blasting, and sometimes the building owner files a lawsuit against the company that perform blasting operations. The blast-vibration problem has been thoroughly investigated in the past and continues to be the subject of ongoing research. In this study, a tunnel construction has been performed by a construction company, according to their contract they must have used drilling & blasting method for excavation in tunnel inlet and outlet portal. The population is very condensed with almost tunnel below in the vicinity houses of one or two floors, typically built with stone masonry and concrete. This situation forces the company to take extreme precautions when they are designing blasts so that the blast effects, which are mainly vibration and aerial waves, do not disturb their surrounding neighbors. For this purpose, the vibration measurement and analysis have been carried out and a new methodology in minimizing the blast induced ground vibrations at the target location, was also applied. Peak particle velocity and dominant frequencies were taken into consideration in analyzing the blast-induced ground vibration. The methodology aims to employ the most suitable time delays among blast-hole groupings to render destructive interference of surface waves at the target location.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.442-449
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• 2003

This study presents a new analysis of blast vibration equations of a bridge structures using a reliability index. Changing the reliability makes each blast vibration equation. The blast equations are divided into three classes, having 50%, 90% and 99.9% at ${\beta}$=0, 1.28 and 3 respectively. In the result of this research, the assumption equations which used ${\beta}$=1.28 is suitable. By using these blast equations, it is possible for users to predict reliable ground vibration values upon demand.

• Smart Structures and Systems
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• v.21 no.5
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• pp.561-569
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• 2018

Ground vibration is one of the most undesirable effects induced by blast operation in mountain tunnels, which could cause negative impacts on the residents living nearby and adjacent structures. The ground vibration effects can be well represented by peak particle velocity (PPV) and corner frequency ($f_c$) on the ground. In this research, the PPV and the corner frequency of the mountain surface above the large-span tunnel of the new Badaling tunnel are observed by using the microseismic monitoring technique. A total of 53 sets of monitoring results caused by the blast inside tunnel are recorded. It is found that the measured values of PPV are lower than the allowable value. The measured values of corner frequency are greater than the natural frequencies of the Great Wall, which will not produce resonant vibration of the Great Wall. The vibration effects of associated parameters on the PPV and corner frequency which include blast charge, rock mass condition, and distance from the blast point to mountain surface, are studied by regression analysis. Empirical formulas are proposed to predict the PPV and the corner frequency of the Great Wall and surface structures due to blast, which can be used to determine the suitable blast charge inside the tunnel.

• Explosives and Blasting
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• v.27 no.1
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• pp.79-87
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• 2009

The regression analysis of the ground vibration data (particle velocity and vibration level) was carried out to find an empirical relation between the vibration velocity (PVS, PPV, $V_V$) and the vibration level. The regression results revealed that the correlation of the blast vibration velocity and vibration level was quite good. It seems that the empirical relation obtained in this research will be applied to evaluating and managing the various environmental vibrations.

• Explosives and Blasting
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• v.22 no.3
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• pp.85-95
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• 2004

A damage criterion by blast vibration & noise has to be established through a engineering view point. Though a blast vibration has effects on human and structure, they have experienced a different damage. Thus, a damage criterion for structure needs to get a peculiar criterion which are different from one for human. At present, blast damage criterions authorized by government are Vibration & Noise Act made by Ministry of Environment and blast damage criterion of specifications for tunnel made by Ministry of Construction & Transportation. Vibration & Noise Act is based on the response of human, and while it has some application problems, it turns out to be partly rational. But, blast damage criterion of specifications for tunnel has unreasonable guidelines. In this article, its problems are reviewed and a alternative blast damage criterion is suggested.

• Explosives and Blasting
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• v.23 no.3
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• pp.1-10
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• 2005

Blast-induced ground vibration nay cause an environmental impact such as neighbour's complaints or damage on adjacent structures and facilities. Complaints associated with blasting have often become a target of public grievances. One of the difficulties to solve the problem is that we do not have a national standard for the acceptance level of blast-induced ground vibration. A peak particle velocity criterion, which was suggested for urbane underground construction, has often been widely used. Efforts have been made to establish more rational criteria. It seems that differing cultures have often differing thresholds of the toleration of vibration, and that technical data or rational grounds for establishing the limits are hardly provided. In this paper, national standards for allowable limit of blast vibration were presented and discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.772-775
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• 2005

Most engineers, related to soil and civil dynamic field, have been interested in the direct dynamic design of building transmitted from soil and rock to structure due to blasting. However it is not easy to estimate the dynamic response of structures due to blasting by using analytical method because of difficulties of soil modeling, prediction of excitation force and so on. In this paper, dynamic analysis have been performed to predict vibration level and evaluate dynamic safety of structure adjacent to tunnel blast and the semi empirical method, which is based on vibration measurement data, has been employed to consider blast vibration characteristics.

• Explosives and Blasting
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• v.29 no.2
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• pp.43-50
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• 2011

This study measured a vibration level at each distance of construction fields where blasts occur using Lion measuring instrument and used BlastmateIII to measure vibration velocity at the same distance. A total 130 blasts occurred with the weight of a total of 5,180 kg and the number of blast holes per blast was 5, 10 and 20. The weight of 4 kg was used for each hole. Vibrations caused by blast was measured at the distance with the same velocity and level. Measurements were carried 15~102 m away from the blast source. and 273 data on vibration velocity and level were obtained from eight measurements. It analysed data on vibration velocity measured based on existing correlation formulas and compared them to real measurements to analyse interrelationship.

• Tunnel and Underground Space
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• v.18 no.4
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• pp.280-288
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• 2008

Since blast-induced vibration may cause serious problem to the rock mass as well as the nearby structures, the prediction of blast-induced vibration and the stability evaluation must be performed before blasting activities. Dynamic analysis using measurement vibration waveform which is measured by bore hole blasting or test blasting has been increased recently in order to analyze the effect of the blast-induced vibration. The waveform made by bore hole blasting has the similar vibration level and duration to those the waveform of sing hole has. However, there can be a little difference in attenuation characteristics with the blast induced vibration waveform in the field. Through the superposition modeling of single hole waveform, I obtained the vibration waveform on the blasting condition changes and conducted dynamic analysis using this waveform in this study.