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Fire resistance assessment of precast fireproof duct slab

프리캐스트 방식 내화풍도슬래브의 화재저항성 평가

  • Choi, Soon-Wook (Underground Space Safety Research Center, Korea Institute of Civil Engineering and Building Technology) ;
  • Kang, Tae-Ho (Underground Space Safety Research Center, Korea Institute of Civil Engineering and Building Technology) ;
  • Lee, Chulho (Underground Space Safety Research Center, Korea Institute of Civil Engineering and Building Technology) ;
  • Kim, Se Kwon (Research Institute, HONG G) ;
  • Kim, Tae Kyun (HONG G) ;
  • Chang, Soo-Ho (Construction Industry Promotion Department, Korea Institute of Civil Engineering and Building Technology)
  • 최순욱 (한국건설기술연구원 지하공간안전연구센터) ;
  • 강태호 (한국건설기술연구원 지하공간안전연구센터) ;
  • 이철호 (한국건설기술연구원 지하공간안전연구센터) ;
  • 김세권 ((주)홍지 기술연구소) ;
  • 김태균 ((주)홍지) ;
  • 장수호 (한국건설기술연구원 건설산업진흥본부)
  • Received : 2020.10.27
  • Accepted : 2020.11.05
  • Published : 2020.11.30

Abstract

In Korea, fireproof performance is evaluated through a series of fire-resistance tests for important structures, and the performance standard follows the guidelines suggested by ITA. The fireproof duct slab manufactured by combining the slab and the fireproof material with a precast method is effective in that it can eliminate the construction time of the fireproof material. In this study, a series of fire resistance tests was performed on the fire test specimens under the RWS fire scenario in order to secure the fire resistance performance of the precast fireproof duct slab. As a result of the test, it was found that the fireproof performance was secured when the thickness of the fireproof material was 30 mm or more. In both fireproof materials and concrete, the rate of temperature change initially increased, then decreased, and then increased again, and the temperature at the inflection point was measured as 110℃ for all fireproof materials and concrete. It is judged that this occurs when the C-S-H (CaO-SiO2-H2O) generated by the hydration reaction in both the fireproof material and concrete is dehydrated.

국내에서는 중요 구조물을 대상으로 별도의 내화시험을 통해 내화성능을 평가하고 있으며, 그 성능기준으로 ITA에서 제시하고 있는 가이드라인을 따르고 있다. 프리캐스트 방식으로 슬래브와 내화재가 일체화되어 제작되는 내화풍도슬래브는 내화재 시공시간을 단축할 수 있다는 점에서 효과적이다. 본 연구에서는 풍도슬래브의 내화성능을 확보하기 위해 RWS화재시나리오 하에서 내화시험체에 대한 화재저항시험을 수행하였다. 시험결과, 내화재 두께가 30 mm 이상에서 내화성능을 확보하는 것으로 나타났다. 내화재와 콘크리트 모두에서 온도 변화율이 초기에 증가했다가 감소하고 다시 증가하는 경향이 나타났으며, 다시 증가하는 변곡점에서의 온도가 모든 내화재와 콘크리트에서 110℃로 측정되었다. 이것은 내화재와 콘크리트가 모두 수화반응에 의해 생성된 C-S-H (CaO-SiO2-H2O)가 탈수되면서 발생하는 것으로 판단된다.

Keywords

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