A procedure to measure the in-situ hygrothermal behavior of earth walls

P. A. Chabriac, A. Fabbri, Jean-Claude Morel, J. P. Laurent, J. Blanc-Gonnet

    Research output: Contribution to journalArticle

    11 Citations (Scopus)
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    Abstract

    Rammed earth is a sustainable material with low embodied energy. However, its development as a building material requires a better evaluation of its moisture-thermal buffering abilities and its mechanical behavior. Both of these properties are known to strongly depend on the amount of water contained in wall pores and its evolution. Thus the aim of this paper is to present a procedure to measure this key parameter in rammed earth or cob walls by using two types of probes operating on the Time Domain Reflectometry (TDR) principle. A calibration procedure for the probes requiring solely four parameters is described. This calibration procedure is then used to monitor the hygrothermal behavior of a rammed earth wall (1.5 m × 1 m × 0.5 m), instrumented by six probes during its manufacture, and submitted to insulated, natural convection and forced convection conditions. These measurements underline the robustness of the calibration procedure over a large range of water content, even if the wall is submitted to quite important temperature variations. They also emphasize the importance of gravity on water content heterogeneity when the saturation is high, as well as the role of liquid-to-vapor phase change on the thermal behavior.
    Original languageEnglish
    Pages (from-to)3002-3020
    JournalMaterials
    Volume7
    Issue number4
    DOIs
    Publication statusPublished - 11 Apr 2014

    Fingerprint

    Earth (planet)
    Calibration
    Water content
    Forced convection
    Natural convection
    Gravitation
    Moisture
    Vapors
    Water
    Liquids
    Temperature
    Hot Temperature

    Bibliographical note

    This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

    Keywords

    • dielectric constant
    • water content measurement
    • rammed earth
    • cob
    • hygrothermal behavior
    • full scale experiments

    Cite this

    Chabriac, P. A., Fabbri, A., Morel, J-C., Laurent, J. P., & Blanc-Gonnet, J. (2014). A procedure to measure the in-situ hygrothermal behavior of earth walls. Materials, 7(4), 3002-3020. https://doi.org/10.3390/ma7043002

    A procedure to measure the in-situ hygrothermal behavior of earth walls. / Chabriac, P. A.; Fabbri, A.; Morel, Jean-Claude; Laurent, J. P.; Blanc-Gonnet, J.

    In: Materials, Vol. 7, No. 4, 11.04.2014, p. 3002-3020.

    Research output: Contribution to journalArticle

    Chabriac, PA, Fabbri, A, Morel, J-C, Laurent, JP & Blanc-Gonnet, J 2014, 'A procedure to measure the in-situ hygrothermal behavior of earth walls' Materials, vol. 7, no. 4, pp. 3002-3020. https://doi.org/10.3390/ma7043002
    Chabriac PA, Fabbri A, Morel J-C, Laurent JP, Blanc-Gonnet J. A procedure to measure the in-situ hygrothermal behavior of earth walls. Materials. 2014 Apr 11;7(4):3002-3020. https://doi.org/10.3390/ma7043002
    Chabriac, P. A. ; Fabbri, A. ; Morel, Jean-Claude ; Laurent, J. P. ; Blanc-Gonnet, J. / A procedure to measure the in-situ hygrothermal behavior of earth walls. In: Materials. 2014 ; Vol. 7, No. 4. pp. 3002-3020.
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