Jordan Journal of Civil Engineering

Study on Soil Water Characteristics of Black Soil, Northeast China


Haiqiang Jiang; Fujun Niu; Heng Zhang; Enliang Wang; Qinguo Ma;


Black soil has strong swell-shrink characteristics due to the change of water content. Permeability and fractal behavior can be reflected by soil water characteristic curve (SWCC). Although many relevant models can calculate the SWCC, the applicability of these models on black soil is unclear. In addition, the prediction of the SWCC is complicated, as the necessary parameters are difficult and time-consuming to measure. In this context, a series of experiments on the SWCC of black soil was conducted in the laboratory. Based on the results and analysis, conclusions were drawn as follows: The pore fractal dimension is strongly correlated with dry density; that is, the larger the dry density is, the greater the fractal dimension becomes. The permeability coefficient decreases with the increasing of the matric suction. The three commonly SWCC models (Fredlund (1994), Van Genuchten (1980) and Gardner (1958)) are appropriate for predicting the SWCC of black soil. Moreover, the optimized van Genuchten model can improve the accuracy of prediction by replacing the model parameters with the formula of dry density. Compared with the van Genuchten model, the absolute value of relative error decreased from 4.50% to 3.75% after optimization.


Black soil, Soil water characteristic curve, Fractal dimension, Permeability coefficient, Dry density, Matric suction