• Tunnel and Underground Space
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• v.14 no.2
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• pp.108-120
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• 2004

Dynamic analysis has been increased recently to analyze the effect of the blasting vibration on the rock mass as well as the surrounding structures. The major input parameter far the general dynamic analysis, however, is merely the blasting pressure which can be obtained from the blasting pressure-time history curves. But in case of the complicate geological condition it is not simple to apply the blasting pressure on the numerical analysis because e ground vibration characteristics should be obtained considering the complexity of ground condition. Therefore the authors tried to use the blasting vibration waveform as an input data This vinylation frequency could be obtained from the test blasting in the Pasir mine, Indonesia. Through the dynamic numerical analysis on the slopes in Pasir, the current situation of this slope could be simulated precisely.

• Tunnel and Underground Space
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• v.2 no.2
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• pp.199-211
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• 1992

Blasting vibrations of 3 quarries and 5 construction sites were measured and investigated with two reference data. Square and cubic root scaled distance were similar in fitness to peak particle velocity of individual blasting site, but the former is better fitted in total. It was suggested that the limit scaled distance for domestic surface blasting be 40kg/$\textrm{cm}^2$ for 10mm/s level and 60kg/$\textrm{cm}^2$ for 5mm/s level, which were lower than the OSM's regulation. Prevailing vibration components were in the order of radial, vertical and transverse directions. Prevailing vibration components were in the order of radial, vertical and transverse directons. Site factors K and m were 242 and -1.283 for all studied area, 357 and -1.348 for construction sites, 118 and -1.160 for quarries. Most prevailing frequency was in the range of 10~2Hz. Overlapping effect of delayed blasting vibrations were insignificant. Vibration history of delayed blasting was longer than simultaneous blasting, and it became longer as measuring distance increased. Wave form and predominant frequencies were more complicated for delayed blasting than instantaneous blasting. The influence of blasting scale and measuring distance were not significant to determine peak particle velocity equation.

• Tunnel and Underground Space
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• v.17 no.6
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• pp.484-492
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• 2007

The blasting vibration prediction in the country is mainly carried out by using the scaled distance method. But, this method needs a real-scale test blasting. The blasting vibration prediction has been performed using the data measured at borehole blasting for the purpose of a geological investigation before beginning a construction of a tunnel. In this prediction method, it is difficult to reflect the propagation characteristics of ground vibration generated from a real-scale blasting. propagation. This paper presents a new method for estimating blasting vibration by using superposed data of single hole blasting waveform with a delay time.

• Explosives and Blasting
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• v.24 no.1
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• pp.1-8
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• 2006

Recently, most of limestone quarries have been not mined by open-pit mining but by underground excavation to reduce environmental pollution. As a result, the size of underground galleries became bigger to maintain mass-production close to open-pit mining. However, the scale of pillars and galleries as well as the excavation methods may induce a few adverse problems for the stability of a mined gallery. In this study, the nomogram analysis and the prediction of rock damage zone induced by blasting were carried out. The testing conditions include concurrent blasting of two adjacent galleries, concurrent blasting of a transport drift and a inclined shaft, sequential blasting of two galleries, and separate blasting for each gallery. For each testing condition, blast vibration velocity was measured and analyzed. From the prediction formulas for blast vibration velocity derived in this study, the maximum depth of rock damage zone induced by blasting were also predicted.

• Tunnel and Underground Space
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• v.9 no.1
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• pp.12-19
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• 1999

In this study, ground vibrations of a surface blasting for golf links and a tunnel blasting for highway construction were measured to investigate the effect of blasting conditions such as total charge and distance from blasting point. In surface blasting, site factor K and n were 74.1 and -1.37, respectively, which were analyzed by means of cube root scaled distance. The more were measuring distance, the higher were absolute value of K and n. Principal frequency was in range of 5~60 Hz in surface blasting, where that of 80 percent was in range of 10~30 Hz. On the other hand it was in range of 25~98 Hz in tunnel blasting, which showed higher than of surface blasting.

• Explosives and Blasting
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• v.37 no.2
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• pp.1-13
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• 2019

In this study, Rock deformation on the splitting surface was investigated by using the finite element code relating to the blasting in urban area. The maximum principal strain according to the blasting detonation pattern was analyzed by the modeled blast section, and deformation of the splitting surface formed by the numerical analysis and the real blasting were compared. As a result, it was found that the maximum principal strain was observed a difference according to the blasting detonation pattern on the splitting surface, and the splitting surface was showed a similar waveform both the numerical analysis and the real blasting.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.11
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• pp.64-69
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• 2020

To determine the effective factors for microparticle blasting with precise sequence position control in the x-axis and y-axis directions, we conducted a statistical experimental analysis of blasted square shapes by considering five condition factors. The control input and output were operated simultaneously by rotation-linear motion conversion and fine particles were blasted onto the aluminum specimen by precise position control driving using multiple execution codes. The micro-driving device used for processing was capable of microparticle blasting and of controlling the system through contact with a limit sensor at high speed and a two-degree-of-freedom driving mechanism. Our experiments were conducted on 1,050 specimens of pure aluminum (containing <1% of other elements). The effects of several factors (e.g., particle and nozzle diameters, blasting pressure, and federate and blasting cycle numbers) on the surface roughness and blasted surface's depth were verified through a statistical experimental analysis by applying the dispersion analysis method. This statistical analysis revealed that the nozzle diameter, the blasting pressure, and the blasting cycle number were the dominant factors.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.150-151
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• 2022

Blasting is a method that uses explosives to crush the ground. This method is a highly efficient ground cleaning method that can secure high efficiency in a short time. However, explosions can damage local properties and produce high noise and vibration. Therefore, it is important to be careful because there are disadvantages such as the occurrence of many complaints from the surrounding area. In this paper measured and analyzed the noise and vibration generated during blasting at the blasting site in Korea. The noise and vibration generated during blasting were measured by ES03303.2b and ES03402.2a at a distance of 6 m, 12 m from the blasting point. As a result of the measurement, there was little difference between small and medium scale except for precision vibration blasting at a distance of 6m, but noise difference according to blasting scale was evident at a distance of 12m. As a result of the measurement, the maximum noise level was reduced to 5.5 dB(A) and the vibration level was reduced to 7.7 dB(V). In the future, the reliability of the test results can be further improved through additional tests, and it is judged that noise and vibration prediction models based on blasting methods, amount of charge, measuring distance, etc. can be developed.

• Explosives and Blasting
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• v.13 no.3
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• pp.7-18
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• 1995

On the Seoul sub-way tunnel works 7-20 site, Cautious blasting works were so effectivelly carried out. The vibration record were under 0.3cm/sec and blasting noise was under 80dB. Which was measured at the ground of house. At a result cautious blasting works under above allowable value was not influenced the structure of house and living conditions. On the architectural survey, They were some hair crack on the wall and floors but this was not a crack from blasting works.

• Explosives and Blasting
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• v.27 no.1
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• pp.53-61
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• 2009

R.O.K's explosive manufacturing source was first black powder (B.P) introduced into Korea Dynasty from China. In 1890, black powder was first used for mining blasting in Masan. Nowadays, a vibration control blasting method using the emulsion explosive has been applid to explosive demolition of building structure, subway and road construction sites. In December, 2006, Korean Government and professional society (KSEE) established the blasting guidelines of Modern Vibration Controlled Blasting Method (MVCBM) which is an unprecedented in the world.