The focus of this paper is directed towards developing models for predicting the soil–water characteristic curves (SWCCs) for coarse- and fine-grained soils taking account influence of hysteresis and various factors such as the stress state and soil structure, respectively. For achieving this objective, several novel models are derived from the pore-size distribution (PoSD) curve of the SWCC and linked to the well-known SWCC fitting equations. Three simple methods are developed from the proposed model that can be used for predicting the scanning SWCCs of coarse-grained soils. A modified SWCC model is built based on the theoretical background developed for the PoSD curve that is capable for predicting the of fine-grained soils taking account influence of the initial water content and stress state. In addition, a coupled SWCC model is proposed that can be used for explaining the influence of multiple soil parameters. The proposed novel, yet simple models can be used in numerical modeling of complex coupled hydromechanical problems and for predicting of various properties of unsaturated soils.

本文的重点是开发用于预测粗粒和细粒土壤的土壤-水特征曲线 (SWCC) 的模型，这些模型分别考虑了滞后效应和应力状态和土壤结构等各种因素的影响。为了实现这一目标，从 SWCC 的孔径分布 (PoSD) 曲线导出了几个新模型，并与众所周知的 SWCC 拟合方程相关联。从所提出的模型中开发了三种简单的方法，可用于预测粗粒土壤的扫描 SWCC。基于为 PoSD 曲线开发的理论背景建立了一个改进的 SWCC 模型，该模型能够预测细粒土壤的初始含水量和应力状态的影响。此外，提出了一种耦合 SWCC 模型，可用于解释多种土壤参数的影响。所提出的新颖而简单的模型可用于复杂耦合流体力学问题的数值模拟和预测非饱和土壤的各种特性。