In this study, Discontinuous Deformation Analysis (DDA) method is extended to simulate Soil-Water Characteristic Curve (SWCC) by considering both capillary water and bound water at the micro-scale. First, a simple and practical bound water model is proposed and incorporated into DDA program to simulate SWCC in the high suction range. Then, to prove the availability of the developed program, the extended DDA is used to simulate the SWCCs of two types of fine sand with kaolin clay in a wide suction range. The simulation results agree with the experimental results, which demonstrate that the extended DDA is an alternative method for simulating and analyzing SWCC of both cohesionless soil and cohesive soil. Finally, one of the influential factors specific surface area is theoretically analyzed. This study provides an approach to simulate the matric suction of unsaturated soil, and the extended DDA could be a potential tool for unsaturated soil research.

在本研究中，不连续变形分析 (DDA) 方法扩展到通过考虑微观尺度的毛细管水和结合水来模拟土壤-水特征曲线 (SWCC)。首先，提出了一个简单实用的结合水模型，并结合到DDA程序中来模拟高吸力范围内的SWCC。然后，为了证明所开发程序的可用性，使用扩展的 DDA 在较宽的吸力范围内模拟了两种含高岭土的细砂的 SWCC。模拟结果与实验结果一致，表明扩展DDA是模拟和分析无粘性土和粘性土SWCC的一种替代方法。最后，对影响因素之一的比表面积进行了理论上的分析。