• 제목/요약/키워드: DDESB

검색결과 3건 처리시간 0.019초

폭발압접에 대한 갱도의 안정성 분석 (Stability Analysis of Mine Drift for Explosive Welding)

  • 양형식;장명환;장형두
    • 화약ㆍ발파
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    • 제28권1호
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    • pp.55-62
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    • 2010
  • 광산의 채광장 활용을 위해 갱도 내에서 폭발압접이 계획되었다. 폭발압접의 입사압력에 의해 영향을 받을 것으로 예상되는 갱도의 천단부와 주변 광주의 안정성 분석 실시하였다. 폭풍압의 예측은 일반식, CONWEP 및 DDESB의 식을 이용하였다. 분석결과 폭발압접이 지속적으로 이뤄진다면 광산 채굴적에 상당한 영향을 줄 수 있을 것으로 판단되었다.

Lead Plate Blast Pressure Meter를 이용한 근거리 기폭의 발파압 계측 (Direct Measurement of Blast Pressure in Near Field with Lead Plate Blast Pressure Meter)

  • 고영훈;장형두;양형식
    • 터널과지하공간
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    • 제22권1호
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    • pp.54-59
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    • 2012
  • 노천에서 폭파실험을 통해 납판 발파압계의 변형량을 계측하였다. 홉킨슨 바 시험장치의 가스 건으로 압력 실험하여 구한 보정 그래프에 계측데이터를 적용하여 폭풍압을 산출하였다. 그 결과를 CONWEP, DDESB 등 여러 가지 폭풍압 예측식과 대비하였다. 근거리 폭풍압의 실 계측 값은 폭풍압 예측식의 결과보다 최대압력이 낮게 나타났지만 거리에 따른 압력감쇠는 폭풍압 예측식보다 완만한 것을 확인할 수 있었다. 이는 기존 이론식으로 추정한 초근접 지점의 발파압은 부정확함을 의미한다.

Investigation of the LPG Gas Explosion of a Welding And Cutting Torch at a Construction Site

  • Lee, Su-kyung;Lee, Jung-hoon;Song, Dong-woo
    • Korean Chemical Engineering Research
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    • 제56권6호
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    • pp.811-818
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    • 2018
  • A fire and explosion accident caused by a liquefied petroleum gas (LPG) welding and cutting torch gas leak occurred 10 m underground at the site of reinforcement work for bridge columns, killing four people and seriously injuring ten. We conducted a comprehensive investigation into the accident to identify the fundamental causes of the explosion by analyzing the structure of the construction site and the properties of propane, which was the main component of LPG welding and cutting work used at the site. The range between the lower and upper explosion limits of leaking LPG for welding and cutting work was examined using Le Chatelier's formula; the behavior of LPG concentration change, which included dispersion and concentration change, was analyzed using the fire dynamic simulator (FDS). We concluded that the primary cause of the accident was combustible LPG that leaked from a welding and cutting torch and formed a explosion range between the lower and upper limits. When the LPG contacted the flame of the welding and cutting torch, LPG explosion occurred. The LPG explosion power calculation was verified by the blast effect computation program developed by the Department of Defense Explosive Safety Board (DDESB). According to the fire simulation results, we concluded that the welding and cutting torch LPG leak caused the gas explosion. This study is useful for safety management to prevent accidents caused by LPG welding and cutting work at construction sites.