• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.5-12
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• 2015

Since blasting noise is impact noise, it will give a sudden shock to the human. In the case, such as the blast vibration, it has given aging buildings and livestock great damage to move the vibration along ground in nearby regions. In this study, the influence of the blasting generated during excavation was analyzed for effects on regional. A couple of field and laboratory surveys about geological were carried out to figure out the geological ratio in the study-performed area. Blast vibration noise was compared to the domestic and abroad case studies and each of the institutions permissible standards established the most appropriate criteria in site condition. The vibration velocity of blasting vibration exploits the values which were measured from test blasting on the ground in order to examine blasting effect. Considering the blasting point as the shortest distance from safety facilities (farms, private houses, etc.), the examination of the influence range, which was derived from the vibration velocity of blasting vibration, was performed to figure out how the point affected the safety facilities. Three-dimensional numerical analysis was performed a time history analysis in order to analyze the behavior of the structure for a dynamic blast load, which was determined in three directions of the blast vibration value. The results of three-dimensional numerical analysis and the blasting effect of blasting vibration estimation equation blasting vibration of impact circle with accompanying test blasting were compared. And the analysis confirmed similar results figures.

• Explosives and Blasting
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• v.20 no.2
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• pp.7-19
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• 2002

The cut is placed high up in the section, the 1st sloping holes below the cut, and divided all the holes located below the 1st sloping holes into a certain area with longitudinal section, to lower pollution made from tunnel blasting. With the sequential blasting machine, after I first blasted holes around the cut holes by a pre-splitting method, blasted the cut area and the 1st sloping holes. The 1st and 2nd sloping holes divided areas are initiated gradually to free face upwards made by the cut. Especially, I pre-splinted contour holes previous blast the before sloping holes from the contours. The ground vibration from the earth surface just over the advance face decreased about 42.0% compare with the down blasting method under the condition of equal charge weight per delay. I controlled the crack and over break of the mother rock by pre-splitting contour holes before blast the first sloping holes from the contours. The peak values of noise and air blast by blasting decreased about 10dB more than the down blasting method. the noise and air blast diminished gradually as a round. The throw distance of the fly rock was decreased about 55%.

• Explosives and Blasting
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• v.30 no.2
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• pp.59-65
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• 2012

This study improved constructability and cost efficiency that are disadvantages of existing a mechanical excavation & similar blasting methods(plasma, gel, etc) and introduced cases of development and practical applications of Low vibration explosives(LoVEX) that minimizes blast vibration. The low vibration explosives(LoVEX) is suitable to Type-1 in standard blasting patterns of Ministry of Land, Transport and Maritime Affairs(MLTM) and delay blasting is possible. Moreover, the low vibration explosives improve construction and work efficiency while the level of vibration is reduced to about 60~70% of normal emulsion explosives. Additionally, this study suggested standard blasting patterns, the prediction equation of blasting vibration, and construction methods.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.55-62
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• 2018

Problems on vibration due to blasting for infrastructure development are getting important because of a civil appeal. Blasting-induced vibration is representative construction pollution, hence, it is possible that a number of environmental damages occur. In this study, borehole test blasting was conducted at Sintanjin area, Daejeon and square root equation with 95% confidence level was proposed for prediction of blasting-induced vibration. The vibration value predicted from this equation was more conservatively evaluated than the values predicted from U.S. Department of Interior, Bureau of Mines (USBM) and Nippon Oil & Fats Co., Ltd. (NOF) equations. Therefore, the proposed equation in this study seems to contribute for safety blast design. However, for optimal blast design, inducing equation for prediction of blasting-induced vibration through the identical test blasting with field construction such as rock slope blasting would be required.

• Tunnel and Underground Space
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• v.4 no.3
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• pp.287-296
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• 1994

Safety-related structures of power plants have to be protected against the effects of possible hazards and natural phenomena. Earthquakes are considered a major dynamic design loading as a requirement of plant design, but the effects of blast-induced vibratons are not. Due to the difficulties of obtaining construction site for new plants, following ones are inevitably being built in the site adjacent to existing power plants. Therefore considerable thought has been recently given to the dynamic loading generated by blasting works near the plants. In this paper, discussed is applicability of existing vibration standards and industrial codes to the blasting works near safety related structures. Also evaluated are the parameters for the safe vibration limits such as measure of vibration level, frequency consideration, structure response, propagation equation, etc.

• Tunnel and Underground Space
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• v.4 no.1
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• pp.38-46
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• 1994

This paper concerns the design of blasts adjacent to structures and facilities. In order to investigate the site characteristics, measurements of in-situ wave propagation and laboratory tests of rock cores taken from the boreholes were carried out. Effects of rock media and delay intervals on ground vibration levels were identified from over sixty measurements of three times of test blasts. For practical use in the field, an empirical propagation equation was derived so as to reflect the characteristics of rock media and delay effects. Safe limits of vibration level for structures were conservatively established based on various suggested criteria. Safe limits for facilities were adopted so that vibration levels induced by blasting should not exceed the allowable limits specified in the manufacturer's installation condition. Suggested were blast pattern and operation to enhance the rock fracturing and to reduce the ground vibration levels under the restricted conditions.

• Tunnel and Underground Space
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• v.18 no.2
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• pp.118-124
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• 2008

Allowable level of blasting vibration for earth retaining wall was examined in this study. Blasting vibration was measured at near field blasting to evaluate the influence of the blasting work to earth retaining wall and rear ground. Although small scale blasting with $0.5{\sim}2.0kg$ explosives per round merely influenced to the structure and ground, but it was suggested to blast at the distance of twice the least burden considering the block movement.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.6
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• pp.959-972
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• 2017

In evaluation of blast-induced vibration, peak particle velocity (PPV) is generally calculated by using attenuation relation curve. Calculated velocity is compared with the value in legal requirements or the standards to determine the stability. Attenuation relation curve varies depending on frequency of test blasting, geological structure of the site and blasting condition, so it is difficult to predict accurately using such an equation. Since PPV is response value from the ground, direct evaluation of the structure is impractical. Because of such a limit, engineers tend to use the commercial numerical analysis program in evaluating the stability of the structure more accurately. However, when simulate the explosion process using existing numerical analysis program, it's never easy to accurately simulate the complex conditions (fracture, crushing, cracks and plastic deformation) around blasting hole. For simulating such a process, the range for modelling will be limited due to the maximum node count and it requires extended calculation time as well. Thus, this study is intended to simulate the elastic energy after fractured zone only, instead of simulating the complex conditions of the rock that results from the blast, and the analysis of response characteristics of the velocity depending on shape and size of the fractured zone was conducted. As a result, difference in velocity and attenuation character were calculated depending on fractured zone around the blast source appeared. Propagation of vibration tended to spread spherically as it is distanced farther from the blast source.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.10
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• pp.1053-1061
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• 2009

The goal of this paper is to investigate the generation characteristics of the main impulsive noise sources generated by the supersonic flow discharging from a muzzle. For this, this paper investigates two fundamental mechanisms to sound generation in shocked flows: shock motion and shock deformation. Shock motion is modeled numerically by examining the interaction of a sound wave with a shock. The numerical approach is validated by comparison with results obtained by linear theory for a small disturbance case. Shock deformations are modeled numerically by examining the interaction of a vortex ring with a blast wave. A numerical approach of a dispersion-relation-preserving(DRP) scheme is used to investigate the sound generation and propagation by their interactions in near-field.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.12
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• pp.1229-1235
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• 2010

Anti-terrorism design for public buildings as well as military facilities is important to minimize the mass casualties from terrorist attacks. Also, well designed glazing and window systems can reduce the potential injury of human caused by scattering fragment of a glazing. In this paper, blast resistant design for glazing and window systems is investigated based on the U.S. Standard. The design procedures include minimum requirements for the design, standard practice for design evaluation of the glazing and standard test method for evaluation of the performance.