Volume 35, Issue 1 (January 2012)

    A New Method for Soil Water Characteristic Curve Measurement Based on Similarities Between Soil Freezing and Drying

    (Received 3 December 2010; accepted 26 June 2011)

    Published Online: 2011

    CODEN: GTJOAD

      Format Pages Price  
    PDF 9 $25   ADD TO CART


    Abstract

    The soil water characteristic curve (SWCC) is the basis to explain a variety of processes in unsaturated soils, ranging from transport phenomena to mechanical behaviors. In this paper, a new method is developed for SWCC estimation based on the similarity between the freezing/thawing process and drying/wetting process in soils. The theoretical basis for this method is first reviewed. The concept of the soil freezing characteristic curve (SFCC) is introduced to describe the relationship between the unfrozen water content and matric suction in frozen soils. SFCC is analogous to SWCC in that both of them describe the energy status of liquid water associated with liquid water content. Relationships between SWCC and SFCC are discussed. To measure the SFCC, a thermo-time domain reflectometry (TDR) sensor was developed which combines both temperature sensors and conventional TDR sensor. The TDR module and algorithm measured the bulk free water content of soils during the freezing/thawing processes, while the built-in thermocouples measured the internal temperature distribution. SFCCs were obtained from the simultaneously measured TDR and temperature data. Experiments were conducted on a few types of soils to validate this new procedure. The SFCC was obtained from thermo-TDR data collected in specimens subjected to a controlled thawing process, while the SWCC was directly measured by ASTM D5298, the filter paper method. Reasonable agreements were found between SWCC and SFCC. The experimental results implied that the SWCC could be estimated from SFCC, which also provided more evidence of the similarity of freezing/thawing processes and desorption/sorption processes.


    Author Information:

    Liu, Zhen
    Case Western Reserve Univ.,

    Zhang, Bin
    Dept. of Civil Engineering, School of Engineering & Technology, China Univ. of Geosciences, Beijing, China, 100083,

    (Bill) Yu, Xiong
    Case Western Reserve Univ.,

    Zhang, Bin
    Case Western Reserve Univ.,

    Tao, Junliang
    Case Western Reserve Univ.,


    Stock #: GTJ103653

    ISSN: 0149-6115

    DOI: 10.1520/GTJ103653

    ASTM International is a member of CrossRef.

    Author
    Title A New Method for Soil Water Characteristic Curve Measurement Based on Similarities Between Soil Freezing and Drying
    Symposium , 0000-00-00
    Committee D18