Nature of Soil–Water Characteristic Curve for Plastic Soils

Determinations of unsaturated soil parameters using experimental procedures are time consuming and difficult. In recent years, the soil–water characteristic curve (SWCC) has become an important tool in the interpretation of the engineering behavior of unsaturated soils. Difficulties associated with determining such parameters have justified the use of indirect determination. This paper presents the general behavior of the SWCC for plastic soils, in terms of gravimetric water content versus soil suction, according to the soil type, and also the stress history of the soil. In order to investigate possible relationships between the liquid limit ( w1 ) , suction capacity and SWCC, data from the literature were collected and analyzed. The present study examined 49 SWCCs from 18 soils. The objectives of the paper were twofold: to contribute to the interpretation and use of the SWCC and to present a simple method for inferring the SWCC for plastic soils, taking into account the stress history of the soil.