Water transport in air-pores

• Autorzy: Tada S.
• Konferencja: 5th International Conference on Autoclaved Aerated Concrete "Securing a sustainable future" to be held at Bydgoszcz to celebrate 60 years of AAC experience in Poland, Bydgoszcz, September 14-17, 2011
• Języki publikacji: EN

Abstrakty

EN

Water transport experiments were performed on AAC with known pore structure and well-controlled moisture content. Specimens with the critical moisture content for freeze/thaw resistance were observed with the cryo-SEM. Evidences were confirmed that the ice segregated on the surface of air-pores as a result of redistribution of unfrozen water coming from the matrix part between air-pores. The standpipe absorptivity test for specimens with an air-pore volume of approx. 45 vol.% while having different mean air-pores diameters showed an abrupt jump of permeability when the mean air-pores diameter was smaller than 0.15 mm or the air-pores connectivity was 20%. In the free water uptake test using a dried AAC specimen, the capillary suction precedes other water transports and saturates the capillaries of 35 vol. % instantly followed by a slow absorption process, i.e. escaping of entrapped air bubbles that controls the subsequent absorption rate.

Słowa kluczowe

EN

autoclaved aerated concrete; air pore; sorption performance; water transport; cryo-SEM

PL

beton komórkowy; tor powietrzny; właściwości sorpcyjne; transport wody; kriometria SEM

• Wydawca: Fundacja Cement, Wapno, Beton
• Czasopismo: Cement Wapno Beton
• Rocznik: 2011
• Tom: nr spec.
• Strony: 60--65
• Opis fizyczny: Bibliogr. 14 poz., il.

Twórcy

autor

Tada S.

• Texte, Inc, Tokyo, Japan,

Bibliografia

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