Evaluating Soil-Water Characteristic Curve Based on Local Porosity Theory

Document Type : Research Paper


1 Associate Professor, Department of Civil Engineering, Faculty of Engineering, Shiraz University

2 Ph.D. Student, Department of Civil Engineering, Shiraz University


Modeling vadose zone, particularly the soil water characteristic curve, plays an essential role in unsaturated soil mechanics. This curve depends on such factors as particle size and distribution. A computational procedure acceptable for the assessment of the soil-water characteristic curve is modeling pore size distribution from particle size distribution. In this paper, a model is proposed that considers the variation in local void ratio and evaluates its effect on the soil-water characteristic curve in granular soils with different particle size distributions. Comparison of the results with experimental data shows that the model will predict the soil-water characteristic curve more accurately if a direct relation is established between local void ratio and particle size.


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