• Explosives and Blasting
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• v.26 no.2
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• pp.77-91
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• 2008

According as demand for superannuated building increases recently, much researches about demolition method of construction are going on. This case study executed to center library building located in Dankook University. Explosives demolition method applied Progressive Collapse. Explosives demolition main blasting floors are 2, 4floor, assistance blasting floor is 1 floor. In the nearest distance (150 m), Vibration measurement result were 0.0302 cm/sec (PPV). Change was not in measurement value is crack gauge which install beforehand.

• Explosives and Blasting
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• v.23 no.3
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• pp.83-89
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• 2005

It follows in deterioration of the steel frame structure and becomes remodeling and removal. The construction work characteristic, economical efficiency and stability environment characteristic are planned and considered hereafter control plan of the steel frame structure which is deteriorated currently to cutting mettled plentifully sued on gas cutting of H beam. However it will not be able to apply from the explosives demolition which is makes a weak instantaneously and then collapses the building at the time. In this study, shape charge was used for cutting of the H-beam. That is the element testing to estimate explosives demolition for steel frame structure. As a result, it is found for single-side rutting method, both-sides rutting methods by H-beam thickness and pre-rutting process. It confirmed an affix method and an ease characteristic by fixing tool. Also, it is shown that air blasting decreased about 8dB(A) in order to reduce air blasting used by sand box. However, it will be required to reduce air blasting little more because explosives demolition will be done in urban site.

• Explosives and Blasting
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• v.27 no.1
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• pp.62-78
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• 2009

Recently, construction techniques have been rapidly developed with reconstruction of old buildings, urban regeneration and efforts of restoring natural ecology, so demolition of deteriorated buildings has been rapidly increasing. Demolition work of building should be executed without damaging surrounding environments according to relevant regulations. There are various demolition methods and among them, explosives demolition is the most practical way for expenses and safety of work. As a part of Daejeon stream ecological restoration project, this thesis is a case of executing demolition of Chung-Ang Department Store which was built 35 years ago as covered structure on the upper part of Daejeon stream with explosives demolition. This structure is 8 stories high, total height of 41.6 m including basement floor, $1,650m^2$ for building area and $18,351m^2$ for total floor area. It is located in the center of Daejeon city where shopping centers and buildings are crowded and main facilities are Daejeon subway (18m), backside shopping center (20m), underground shopping center(15m), Mokchuk bridge, Eunjung bridge(0.25m) and fiber-optic cable(0.25m). In this project, implosion was selected for explosives demolition methods by considering this area being a busy urban area, and this project was executed after examining collapse movement of structure in advance using simulation program not to damage main facilities. Total 80kg of explosives and 1,000 detonators were being used. This project will be a good case of executing explosives demolition successfully by applying implosion on urban area in the country.

• Explosives and Blasting
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• v.38 no.2
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• pp.13-21
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• 2020

The shaped charge was used in explosive demolition of a steel frame structure, but it was often not used because it was limited to use and impossible to supply at domestic and overseas. Existing linear shaped charge did not have sufficient cutting performance to cut steel frame structures with a huge scale and thick steel plate. To solve these problems, we produced a device that could generate metal jets using industrial explosives of high detonation velocity and pressure. In this study, we made a charging container of three types which applicable to explosive demolition of steel frame structures. The experiment of cutting performances was carried out to evaluate the effect of cutting of charging containers on the various thicknesses of the H-beam and steel plate. As a result of the experiment, sufficient cutting performance was confirmed.

• Explosives and Blasting
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• v.22 no.1
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• pp.33-43
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• 2004

In this study, a comparison was made between the resulting behaviors of scaled model test and particle flow analysis for blasting demolition of a reinforced concrete structure. For the test and analysis, a progressive failure of a five-story structure was considered. The dimension analysis was carried out to properly scale down the real structure into the laboratory size. The test model was made of the mixture of gypsum, sand and water along with soldering lead to analogy reinforcing steel bars. The ratio of mixing components was chosen to best represent the scaled down strength and deformation modulus. The columns and girders of the structure were precasted in the laboratory and assembled right before the blasting test. The numerical analysis of the blasting demolition was carried out using PFC2D (Particle Flow Analysis 2-Dimension by Itasca). The results of the blasting of concrete lahmen structure showed roughly identical demolition behavior between scaled model test and numerical test. For the blasting of the reinforced concrete structure, the results were more identical and closer to the real demolition behavior, since the demolition behavior was better represented in this case due to the increased tensile strength of the component.

• Explosives and Blasting
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• v.31 no.1
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• pp.1-10
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• 2013

In blasting demolition, a method would be chosen among many depends on shape and system of a structure and its surround. To demolish using explosives a structure, which is asymmetric and with high aspect ratio, pre-weakening, explosive locations, detonating delay, and surround conditions are needed to be considered in front to design blasting demolition plan. In this study, to over turn asymmetric and high aspect ratio structure in safe, a simulation using a software named Extreme Loadings for Structures, ELS, had performed. In results, it is achieved optimized pre-weakening shapes and locations, which prevent kick back motion of the structure when it collapse, by analyzing moment distribution caused by pre-weakening. And of structural collapse and by minimizing asymmetric structure's torsional moment. Also, after the demolition, simulation results are also compared with actual collapse behavior. In results, it is confirmed the accuracy of collapse behaviour simulation results, and in blasting demolition, kick back motion can be controled by adjusting pre-weakening shape and location, and the torsional moment of an asymmetric structure also can be solved by optimizing detonation locations and its time intervals.

• Explosives and Blasting
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• v.16 no.2
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• pp.55-67
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• 1998

• Proceedings of the KSEE Conference
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• 2009.10a
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• pp.83-86
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• 2009

• Explosives and Blasting
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• v.37 no.1
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• pp.34-47
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• 2019

This case study is concerned with the project of the explosive demolition for the DCRE Incheon plant located in Hakik district in Incheon city. The building was severely aging due to the high temperature and sea winds of hundreds of degrees emitted by chimney-shaped steel structures inside the building. Due to this, the concrete of the column and the beam fell off and rusted rebar were exposed, and some of the slabs were severely damaged, making it difficult for workers to access the structure. Therefore, it is not possible to apply a mechanical demolition method in which heavy equipment enters the interior of the building, and an explosive demolition method was applied to allow the building to be demolished without dismantling the internal facilities of the building. The order of blasting proceeded in the order of (1) building ${\rightarrow}$ (2) chimney 2 ${\rightarrow}$ (3) chimney 1. A total of 406 electronic detonators (Unitronic 600) was used to sequentially initiate the explosives installed at appropriate in building and chimneys.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.87-88
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• 2023

서해안 최고의 동백정해수욕장과 마량리 동백나무숲은 1970년대 오일쇼크 이후 에너지 자립을 위해 발전소를 건설하면서 사라졌다. 그 당시 준공된 화력발전소는 전력공급 이라는 소임을 완수하고 2021년 부터 동백정의 아름다운 옛 모습 그대로 지역주민에게 돌려 주기위한 친환경 사업으로 발전소 철거공사를 시작, 동백정 복원공사를 추진 하기로 했다. 고층 및 중량물의 건축물 및 구조물을 안전하게 해체하기 위해서는 국내 최초 발전소 철골구조물에 대한 발파·전도공법을 채택 하였다. 철거작업은 고위험 공종으로 참여 주체인 발주자, 설계자, 감리자, 시공자 및 근로자 전 계층의 참여로 사전 위험성평가를 통해 근원의 위험요인 발굴 및 안전대책 수립, 수립된 안전대책 100% 이행을 통해 무재해 준공 달성 하기를 기대한다.