• 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.

• Explosives and Blasting
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• v.24 no.1
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• pp.57-62
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• 2006

The typical blasting method adopted in Pasir Coal Mine is a surface blasting technique with a single free face. It means that there is only one free face, which is usually the ground surface. This kind of blasting method is easy to use but inevitably causes enormous ground vibrations, which, in turn, can affect the stability of the slopes comprising the various boundaries of the open pit mine. In addition, the method also has the problem of lowering the blast efficiency compared to other methods such as bench blasting methods or ones with more than two free faces. In this respect, a project was launched to develop a new blasting method that is suitable for controling the ground vibration and enhancing the blast efficiency. As a part of the project, authors investigated the current blasting method as well as the overall pit developing process in the mine, and established some important guidelines that should be observed during the whole development process. This paper presents the details of the typical blasting pattern and the pit developing method in the mine, and suggests the guidelines determined from the results of the observations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.310-315
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• 2017

Although studies evaluating the effects of the blasting vibration on the adjacent structures from various angles have continued, cases of securing the safety of the adjacent buildings and researching the proper blasting method for the field condition by analyzing the vibration waveform of the measuring field while performing the open pit blasting are poor. Therefore, it is necessary to present a remedy for blasting pattern selection through test blasting that is appropriate for field conditions, and is economical and efficient. In this study, open pit blasting work was conducted based on the separation distance applied according to the standard blasting method by test blasting and the vibration regulation standard in the road expansion construction site to measure the blasting vibration value, and the vibration prediction equation by blasting methods was examined using a regression analysis computer program to calculate K, N, and R of the confidence level 95%. By setting the blasting allowed vibration standard of the test blasting target area to 0.3cm/sec, and the charring weight and blasting method by the separation distances according to the blasting vibration estimation equation of the open pit blasting guideline and the blasting vibration estimation equation of the test blasting were compared/analyzed, it was possible to identify the factors that increased the working expenses. In addition, the measurement and analysis of the adjacent structures during open pit blasting and the blasting vibration were performed after selecting the most adjacent structure to the open pit blasting spot to analyze the problems on the test blasting procedure and analysis method in the open pit blasting design/construction guidelines, which appeared in the process of completing open pit blasting construction, and a remedy is presented.

• Tunnel and Underground Space
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• v.23 no.6
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• pp.521-537
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• 2013

While microseismicity induced by hydraulic stimulation carried out for EGS is useful means in estimating the range of permeability increase, it also affect surface structures and environments. In order to establish a mitigation plan for microseismicity triggered by hydraulic stimulation, we reviewed world-wide guidelines on the impact of ground vibration on the surface structure and human environment by blasting. Case studies from Europe and USA on the microseismicity by hydraulic stimulation are presented and suggestions are made for the guidelines on ground vibration by hydraulic stimulation for the ongoing Pohang EGS project.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.3
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• pp.419-429
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• 2019

The characteristics of ground vibration have been analyzed by test blasting in southern region of Jeju (layered ground consisting of basalt and clinker). By grasping the principal component of ground vibration and depriving the prediction equations of ground vibration, the propagation characteristics of ground vibration have been compared to the domestic design guidelines. Ground vibration in layered ground has a small amplitude at a short distance. However, it has been confirmed that the vibration energy is transmitted further by virtue of the low attenuation of the ground vibration as it goes to a longer distance. Moreover, the frequency has been confirmed to be low frequency band. The outcome has been defined that it resulted because the clinker layer with a large pore transforms the blasting energy seismic wave with high frequency into a low frequency wave having a long waveform period. In addition, the limits of design guidelines were identified by comparing the ground vibration of Jeju and other bedrock areas. Thus, the necessity of the development of the prediction equations of ground vibration utilized in design that reflect the characteristics of the area has been suggested.

• Explosives and Blasting
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• v.20 no.4
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• pp.29-37
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• 2002

발파진동 및 소음은 일반적으로 발생원인이 사회간접자본의 건설이나 자원 의 개발이라는 공익성과 관련되는 것이 대부분이다. 최근에는 환경문제에 대한 관심이 높아지면서 발파진동이나 소음에 대한 관심이 높고, 또한 많은 민원이 발생되고 있다. 아무튼 발파진동의 측정은 발파에 의해 발생하는 지반 및 구조물의 진동을 파악하여 발파진동 규제기준의 수행 여부를 평가하거나 또는 발파성능을 평가할 목적으로 관련 기관들에 의해 진동측정이 실시되고 있다. 따라서 규정의 준수에 대한 판정은 발파소음과 지반진동 측정의 정확도와 신뢰도에 의존하게 된다. 그러나 발파진동측정에 대한 통일적인 방법이나 지침이 없기 때문에 현장실무에서 측정방법이나 자료처리방법 등에 많은 어려움이 따르고 있다. 따라서 ISEE의 발파진동측정을 위한 실무지침을 중심으로 진동계측자료가 신뢰성을 보장하기 위한 작업의 일환으로 발파진동 측정시 고려해야 할 사항들에 대해 고찰함으로써 발파진동 측정방법에 대한 이해를 높이고자 한다.

• 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.30 no.1
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• pp.29-36
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• 2012

In this study, the influence of priming location inside a blast hole on the ground vibration has been studied. In most of the previous studies dealing with the ground vibration, the effect of priming location in a blast hole was usually considered in a limited way. Thus, it seems that the results of the studies can be applicable only to the relevant sites. Considering the fact that the mechanism of ground vibration caused by blasting is quite complex, the priming location can have a considerable effect on the ground vibration in certain situations and be an important parameter in a blasting design. To identify the characteristics of the wave propagation according to priming locations, total 72 test blasts were carried out with different spacing, burden, drilling length, and charge, and prediction equations were derived. The characteristics of ground vibration, which was changed according to the priming location, was analyzed by using the nomogram of peak particle velocity (PPV) record. Attenuation relations, which were also dependent on the priming location, were analyzed. In this case, four different amounts of charge, that is, 0.5, 1.6, 5, and 15 kg, were used for the test. This criterion of charge amount is specified in the "Blasting design and construction guidelines to road construction" by the Ministry of Land, Transport and Maritime Affairs of Korea.

• Explosives and Blasting
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• v.41 no.3
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• pp.73-92
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• 2023

With the increase of risk of gas explosion, various methods for indirectly estimating the explosion paramaters, which are required for the prediction of gas explosion scale and impact. In this study, the characteristics of the most frequently used methods such as TNT equivalent method, TNO multi-energy method, and BST method and the processes for determining the parameters of the methods were compared. In the case of TNT equivalent method, an adequate selection of the efficiency factor for various conditions such as the type of vapor cloud explosion and explosion material is needed. There is no objective guidelines for the selection of class number in TNO multi-energy method and it is not possible to estimate negative overpressure. It was found that there were some mistakes in the reported parameter values and suggested corrected values. BST method provides more detailed guidelines for the estimation of the explosion parameters including negative overpressure, but the graphs used in this methods are not clear. In order to overcome the problem, the graphs were redrawn. A more convenient estimation of explosion parameters with the numerical expression of the redrawn graphs will be available in the future.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.531-537
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• 1998

Recently, the pile driving or blasting works are increasingly done in many areas to perform large scale construction projects. The vibrations from these blasting works may affect the properties of concrete, especially young concrete. The purpose of present study is to explore the effects of vibration at early ages on the properties of concrete. To this end, comprehensive experimental study is conducted in the present study. The major test variables are peak particle velocity or vibration velocity and the age at vibration. The compressive strengths and bond strengths are measured for all the specimens at 28days after casting. The duration of vibration is fixed to 30 minutes for all cases. The results indicate that the strength increases for vibration velocity less than about 0.25cm/sec and decreases for vibration velocity larger than 0.5cm/sec. The effect of age at vibration is not pronounced and shows almost similar behavior for the age at vibration of 0 to 12 hours range. The present study provides some important guidelines to control the construction or vehicle vibrations for the concrete at very early ages.