New Prediction Model for SWCC of Expansive Soil Considering Drying and Wetting Cycles

• Published in: Journal of mining science Vol. 57; no. 3; pp. 393 - 404
• Main Authors: Ma, Shaokun, Huang, Xiao, Duan, Zhibo, Ma, Min, Shao, Yu
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.05.2021; Springer; Springer Nature B.V
• Subjects: Curve fitting; Cycles; Drying; Earth and Environmental Science; Earth Sciences; Expansive soils; Geomechanics; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Mineral Resources; Prediction models; Soil; Soil testing; Soil water; Volcanic ash; Volcanic soils; Wetting; Nanning expansive soil; drying and wetting cycles; predictive model; soil–water characteristic curve
• ISSN: 1062-7391; 1573-8736
• DOI: 10.1134/S1062739121030054

The structural characteristics of expansive soil is susceptible to repeated drying and wetting cycles caused by seasonal periodical changes. In this paper, the characteristics of Nanning expansive soil were studied, and the soil–water characteristic curves of Nanning expansive soil under multiple drying and wetting cycles were obtained by adopt several known equations. Furthermore, a new prediction model considering two factors was proposed basing on the Van Genuchten model. The new model overcomes the shortcomings of the previous model which considers only matrix suction. It can reasonably consider 2 factors including the matrix suction and the number of drying and wetting cycles. The model can establish a general equation for the soil–water characteristic curve with the same fitting parameters in comparison with the previous model, which can greatly reduce workload of the measurement. In addition, the application of the improved model was broadened by comparing the fitting results and test data of expansive soils of Nanyang and volcanic ash soil.