《International Journal of Geomechanics》刊登了“一种新的土—水特征曲线及其在非饱和土有限元中的应用”

作者：Shada H. Krishnapillai，Nadarajah Ravichandran

刊物：《International Journal of Geomechanics》，12卷第3期，209-219页

关键字：土—水特征曲线；非饱和土；低饱和度的土水特征曲线；土水特征曲线的一般方程；土水特征曲线的比较

摘要：在许多基本的方程中，水分与基质吸力的关系叫做土水特征曲线，是有限元方法模拟非饱和土的动力特征时需要的最重要的关系之一。本研究发现了一种使用了包括最大可能基质吸力在内的四个拟合参数的新土水特征曲线。新的土水特征曲线，适用于各种土的实验数据在一系列饱和度下基质吸力的预测，特别是对于高基质吸力（超过1000kPa）预测较准，可以作为一个新模型使用。Brooks、Corey,、van Genuchten、Fredlund 和Xing模型对低饱和度下预测高基质吸力是不足的。将上述模型与新模型应用于一个模拟非饱和土的动态特征和静态、动态问题的简化有限元程序中，通过对数值稳定性等的对比分析，结果表明：对于中等的饱和度，所有模型可以得到相似的结果，但对于低饱和度，新模型预测的基质吸力变量与其他模型的预测结果不同。

New Soil-Water Characteristic Curve and Its Performance in the Finite-Element Simulation of Unsaturated Soils

Author: Shada H. Krishnapillai, Nadarajah Ravichandran

Journal: International Journal of Geomechanics，Volume 12，Number 3,209-219

Key word: Soil-water characteristic curve; Unsaturated soils; SWCC for low degree of saturation;General equation for soil-water characteristic curve;Comparison of soil-water characteristic curves

Abstract: Among the many constitutive equations, the moisture-suction relationship, also known as the soil-water characteristic curve (SWCC), is one of the important relationships needed for modeling the dynamics of unsaturated soils using the finite-element method. In this study, a new SWCC equation is developed that uses four fitting parameters including the maximum possible suction. The new model predicts the experimental data of various soils well for a wide range of degrees of saturation (DOS), especially in high suction (above 10,000kPa ). Predicting the higher suction at low DOS is one of the deficiencies of the widely used Brooks and Corey, van Genuchten, and Fredlund and Xing models. The numerical stability and performance of the proposed, and other widely used models, are investigated by implementing these models within in a simplified finite-element program for the dynamics of unsaturated soil and simulating static and dynamic problems. For the midrange DOS, all of the aforementioned models predict similar responses. However, at low DOS the new model predicts the suction variations well compared with the other models.

原文链接：http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GM.1943-5622.0000132