Prediction of the thermal spalling risk of concrete structures exposed to high temperatures

• Autorzy: Gawin, D. , Pesavento, F.
• Języki publikacji: EN

Abstrakty

EN

A very characteristic mode of concrete damage at high temperature, especially for the materials characterized by a low intrinsic permeability, like for example HPC or UHPC, is so called thermal spalling. In this paper the results of simulations performed with a mathematical model, which considers concrete as multiphase porous material, are applied to define some spalling indexes based on various collapse mechanisms. A validation of the quantities proposed, carried out by means of a comparison with some experimental test results, is presented. Moreover, the results of a simulation dealing with a structural element exposed to a parametric fire, including a cooling phase, usually not considered in analyses, is described and discussed.

PL

Termiczne odpryskiwanie betonu (ang. thermal spalling) jest bardzo charakterystyczną formą zniszczenia tego materiału pod wpływem wysokiej temperatury. Zagrożone są zwłaszcza materiały o niskiej przepuszczalności, jak na przykład betony wysokiej i bardzo wysokiej wytrzymałości. W niniejszej pracy, bazując na modelu matematycznym betonu, traktowanego jako wielofazowy materiał porowaty, zdefiniowano pewne liczby kryterialne (tzw. indeksy spallingu), które charakteryzują niebezpieczeństwo wystąpienia termicznego odpryskiwania betonu, przy założeniu różnych mechanizmów zniszczenia materiału. Przedstawiono także wyniki eksperymentalnej weryfikacji zaproponowanych kryteriów zniszczenia betonu w wysokiej temperaturze. Ponadto opisano i przedyskutowano wyniki symulacji dotyczących betonowych elementów konstrukcyjnych, poddanych działaniu parametrycznego pożaru, z uwzględnieniem fazy studzenia konstrukcji.

Słowa kluczowe

PL

beton; parametryczny pożar; termiczne odpryskiwanie betonu; niszczenie materiału

EN

thermal spalling; concrete; parametric fire; damage material

• Czasopismo: Architecture Civil Engineering Environment
• Rocznik: 2009
• Tom: Vol. 2, no. 1
• Strony: 49-60
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Gawin, D.

autor

Pesavento, F.

• Technical University of Lodz, Lodz, Poland,

Bibliografia

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