[01] Sabri Kanzari, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia. [02] Mourad Rezig, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia. [03] Béchir Ben Nouna, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia.

Determination of the hydraulic properties of unsaturated soils is essential for the modeling of water flow and solutes transport. Methods of measuring these parameters are often expensive. In this study, a laboratory experiment is presented for the characterization of the hydraulic properties based on the principle of the evaporation method. It is based on following the variation of the water content by the gravimetric method and the pressure head by a tensiometer along a drying cycle of a small sample of soil. The measured retention curves are adjusted on the model of van Genuchten by the RETC software and are then compared with values measured by the pressure chamber method (reference method). The statistical evaluation shows the validity of this simple method for the measurement of the retention curves of unsaturated soils and for the estimation of the hydraulic properties.

Unsaturated Soils, Hydraulic Properites, Parameter Optimization, RETC, Soil Retention Curve

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