Comparative study of soil water characteristic curve prediction methods

2012-06-30
Ahmadiadli, Mohammad
Huvaj Sarıhan, Nejan
Toker, Nabi Kartal
Kürkçü, Mefküre Gamze
The soil-water characteristic curve (SWCC), which defines the relation between soil suction and water content, plays a key role in geotechnical studies of the unsaturated soils. Some researchers such as Brooks & Corey (1968), Van Genuchten (1982) and Fredlund& Xing (1994) have proposed curve fitting equations for SWCC. Fitting equations to the laboratory test data obtained from direct measurement of water content versus changes in matric suction is the most reliable method, but it is expensive and time consuming. Alternatively, there are indirect approaches, which estimate SWCC based on the particle size distribution (PSD) in granular soils and plasticity index in fine grained soils. In this research, we are presenting the drying SWCC of five different soils obtained from laboratory pressure plate and hanging column tests (according to ASTM D 6836, methods A & C), together with application of (1) curve-fitting methods, and (2) SWCC estimation methods based on particle size distribution and plasticity index, proposed in the literature. The materials used in this study are a sand specimen, a specimen of silt and three specimens of clay. We compare different curve-fitting methods and predicted SWCCs with the laboratory data. We found that except Gardner (1958), curve-fitting methods can successfully model the SWCC. We also concluded that any of Fredlund& Wilson (1997), Scheinost (1996), Vereecken (1989) and Arya& Paris (1981) pedo-transfer functions (PTFs) can predict the SWCC somewhat better than the rest of the prediction methods in any of the five soils and none of them is the single best for all these soils.

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Citation Formats
M. Ahmadiadli, N. Huvaj Sarıhan, N. K. Toker, and M. G. Kürkçü, “Comparative study of soil water characteristic curve prediction methods,” 2012, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/76987.