• Title/Summary/Keyword: 내화구조

Search Result 481, Processing Time 0.025 seconds

Fire resistance assessment of precast fireproof duct slab (프리캐스트 방식 내화풍도슬래브의 화재저항성 평가)

  • Choi, Soon-Wook;Kang, Tae-Ho;Lee, Chulho;Kim, Se Kwon;Kim, Tae Kyun;Chang, Soo-Ho
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.22 no.6
    • /
    • pp.669-680
    • /
    • 2020

  • 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.

  • https://doi.org/10.9711/KTAJ.2020.22.6.669 인용 PDF KSCI

Enhancement of the Life of Refractories through the Operational Experience of Plasma Torch Melter (플라즈마토치 용융로 운전경험을 통한 내화물 수명 증진 방안)

  • Moon, Young Pyo;Choi, Jang Young
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.14 no.2
    • /
    • pp.169-178
    • /
    • 2016

  • The properties of wastes for melting need to be considered to minimize the maintenance of refractory and to discharge the molten slags smoothly from a plasma torch melter. When the nonflammable wastes from nuclear facilities such as concrete debris, glass, sand, etc., are melted, they become acid slags with low basicity since the chemical composition has much more acid oxides than basic oxides. A molten slag does not have good characteristics of discharge and is mainly responsible for the refractory erosion due to its low liquidity. In case of a stationary plasma torch melter with a slant tapping port on the wall, a fixed amount of molten slags remains inside of tapping hole as well as the melter inside after tapping out. Nonmetallic slags keep the temperature higher than melting point of metal because metallic slags located on the bottom of melter by specific gravity difference are simultaneously melted when dual mode plasma torch operates in transferred mode. In order to minimize the refractory erosion, the compatible refractories are selected considering the temperature inside the melter and the melting behavior of slags whether to contact or noncontact with molten slags. An acidic refractory shall not be installed in adjacent to a basic refractory for the resistibility against corrosion.

  • https://doi.org/10.7733/jnfcwt.2016.14.2.169 인용 PDF KSCI