Pore size distribution effects on the thermal conductivity of light weight autoclaved aerated concrete

• Autorzy: Kreft, O. , Hausmann, J. , Hubalkova, J. , Aneziris, C. G. , Straube, B. , Schoch, T.
• 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

Aim of the present study was to correlate thermal conductivities of highly porous autoclaved aerated concrete (apparent density < 100 kg/m3) with appendant micro- and nano-structural properties. AAC specimens with approximate apparent densities, but different pore size distributions were fabricated through utilizing specially selected, surface active additives when preparing the slurry of raw materials, aluminum and water. The main focus of this study is on the quantitative analysis of size and morphology of both pores and solid skeleton by 3D X-ray tomography (CT) and scanning electron microscopy (SEM). Moreover, specific surface areas and pore size distributions were determined by the methods of gas adsorption and mercury porosimetry. Apparent thermal conductivities depend on the number of pores, pore size distributions and thicknesses of the separating walls of the solid skeleton. The present study provides further inside in the mechanisms of heat transfer in light weight autoclaved aerated concrete.

Słowa kluczowe

PL

beton komórkowy małej gęstości; rozkład wielkości porów; przewodność cieplna; analiza strukturalna; mikrostruktura

EN

low density autoclaved aerated concrete; pore size distribution; thermal conductivity; structural analysis; microstructure

• Czasopismo: Cement Wapno Beton
• Rocznik: 2011
• Tom: nr spec.
• Strony: 49-52
• Opis fizyczny: Bibliogr. 10 poz., il.

Twórcy

autor

Kreft, O.

autor

Hausmann, J.

autor

Hubalkova, J.

autor

Aneziris, C. G.

autor

Straube, B.

autor

Schoch, T.

• Xella Technology and Research, Department of Product-and Process Research, Gregor-vonBruck-Ring 9 A, D-14822 Bruck & Hohes Steinfeld 1, D-14797 Kloster Lehnin, Germany

Bibliografia

• [1] Narayanan N., Ramamurthy K., 2000. Structure and properties of aerated concrete: a review. Cem. Concr. Comp. 22, 321-329.
• [2] Kreft O., Schoch T., 2010. Alitinform. The Influence Of Moisture On The Thermal Conductivity Of AAC. 1 (13), 60-65.
• [3] Tran L., Strahlungseffekte bei instationären Heizdraht-messungen an porösen Wärmedämmstoffen. Dissertation. TU Bergakademie Freiberg, Germany, 2002.
• [4] Bave G., Aerated light weight concrete-current technology. In: Proceedings of the Second International Symposium on Lightweight Concretes- London, 1980.
• [5] YTONG Multipor Mineraldämmplatte, European Technical Approval ETA05/0093 (valid through May 8, 2015)
• [6] Zürn S.G., Einfluss der Sandminerale auf die Bildung von Calcium-silikathydraten (C-S-H-Phasen), das Gefüge und die mechanischen Eigenschaften von Porenbetonprodukten. Dissertation. Ludwig-Maximilians-Universität München, Logos Verlag Berlin, 1997.
• [7] Prim P., Witmann F.H., Structure and water absorption of aerateid concrete. In: Wittmann F. H., editor. Proceedings Autoclaved Aerated Concrete, moisture and Properties. Elsevier, Amsterdam. 43-53,1983.
• [8] Caty O., 2008. Modelling the properties of closed-cell cellular materials from tomography images using finite shell elements. Acta Materialia. 57, 5524-5543
• [9] Alexanderson J., 1979- Relations between structure and mechanical properties of autoclaved aerated concrete. Cem. Concr. Res. 9 (4), 507-514
• [10] Myers D., Surfaces, Interfaces And Colloids. Principles and Applications (2ed., Wiley-VCH, New York, 1999.