Coupled Heat and Moisture Flow in Unsaturated Swelling Clay Barriers

    Volume 19, Issue 2 (June 1996)

    ISSN: 0149-6115

    CODEN: GTJOAD

    Page Count: 9


    Mohamed, AMO
    Associate director, Geotechnical Research Centre, faculty lecturer, Civil Engineering and Applied Mechanics, McGill University, Montreal, Quebec,

    Yong, RN
    Professor, McGill University, Montreal, Quebec

    Onofrei, CI
    Engineering analyst, Fuel Waste Technology, Atomic Energy of Canada Limited Research, Whiteshell Laboratories, Pinawa, Manitoba

    Kjartanson, BH
    Assistant professor, Iowa State University, Ames, IA

    Abstract

    The main thermodynamic forces active in the near field of a nuclear fuel waste multiple barrier system during the unsaturated stage are the gradients of temperature, fluid pressure, and chemical potentials. The processes that have a direct impact on the transport mechanism of heat and moisture within the clay-based compacted buffer material are coupled. The major problems in describing coupled heat and moisture flow (CHMF) in unsaturated swelling clay barriers are the lack of experimental data and the lack of a method to estimate CHMF diffusivity parameters (CHMF-DIPAR).

    This paper presents the experimental procedures, the analysis of experimental data, and a method of determining CHMF-DIPAR. Several series of one-dimensional tests were performed to examine the transient temperature and moisture flow in buffer material compacted at a dry density of 1.67 Mg/m3 and optimum volumetric moisture content (VMC) of 0.28. CHMF-DIPAR were calculated using the measured temperature and moisture distributions combined with an analytical solution of CHMF equation and a square-root time (SQRT) technique.


    Paper ID: GTJ10338J

    DOI: 10.1520/GTJ10338J

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    Author
    Title Coupled Heat and Moisture Flow in Unsaturated Swelling Clay Barriers
    Symposium , 0000-00-00
    Committee D18