非饱和土的修正SFG模型研究

刘艳; 赵成刚; 韦昌富

非饱和土的修正SFG模型研究 English Version

1.中科院武汉岩土力学研究所岩土力学与工程国家重点试验室，湖北武汉 430071；2.北京交通大学土建学院岩土所，北京 100044

基金项目: 国家自然科学基金项目（51108022，11072255，51078019）

详细信息

作者简介:
刘艳(1983– )，女，博士后，主要从事非饱和土力学方面的研究工作。

中图分类号: TU43
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出版历程
- 收稿日期: 2011-08-25
- 发布日期: 2012-08-19

Modified SFG model for unsaturated soils

(1. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China; 2. School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China)

摘要

摘要: 从非饱和土的有效应力出发，对SFG模型进行了修正，将饱和度的影响引入到了模型当中，使得模型在不增加参数的同时可以反映更多的实验现象。首先简单介绍了SFG模型。然后以功的表达式推导得到的非饱和土有效应力为基础给出了非饱和土的体变方程，在饱和阶段该方程可以自动退化为饱和土的体变方程。结合土水特征曲线方程，推导得到了修正模型的加载湿陷屈服面方程，由此得到的屈服面方程不仅是吸力的函数，同时也是饱和度的函数。屈服面可以连续光滑地从饱和状态过渡到非饱和状态，并可以预测干燥时出现塑性变形的现象。此外它还可以反映SFG模型无法反映的现象，即考虑饱和度的影响，对于吸力相同饱和度不同的土样，给出的屈服应力将不同。最后利用已有试验数据对修正模型进行了验证，说明了修正模型与试验结果是相符的。
- 非饱和土 /
- SFG模型 /
- 饱和度 /
- 有效应力
Abstract: A modified SFG model is developed based on the principle of effective stress. With the effective stress of unsaturated soils deduced from the expression of input work, the degree of saturation is naturally introduced into the proposed model without any additional parameters. After a simple introduction to the SFG model, the volume-change behaviors and the soil-water characteristics are discussed, and then the loading collapse curve is formulated. The loading collapse yield equation in the modified model is a function not only of suction, but also of the current degree of saturation. The yield surface provides a smooth transition between saturated and unsaturated states, which is convenient for simulating the plastic deformation during drying process. The simulated results of the modified model are compared with the experimental data available in literatures, showing that the modified model agrees well with the experimental results. Compared with the original SFG model, the new model yields better results at different degrees of saturation.
- unsaturated soils /
- SFG model /
- degree of saturation /
- effective stress

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参考文献(12)

[1]	ALONSO E E, GENS A, JOSA A. A constitutive model for partially saturated soils[J]. Géotechnique, 1990, 40(3): 405–430.
[2]	殷宗泽, 周建, 赵仲辉, 等. 非饱和土本构关系及变形计算[J]. 岩土工程学报, 2006, 28(2): 137–146. (YIN Zong-ze, ZHOU Jian, CHIU C F, et al. Constitutive relations and deformation calculation for unsaturated soils[J]. Chinese Journal of Geotechnical Engineering, 2006, 28(2): 137–146. (in Chinese))
[3]	SHENG D C, FREDLUND D G, GENS A. A new modelling approach for unsaturated soils using independent stress variables[J]. Canadian Geotechnical Journal, 2008, 45: 511–534.
[4]	GALLIPOLI D, GENS A, SHARMA R, et al. An elasto-plastic model for unsaturated soil incorporating the effects of suction and degree of saturation on mechanical behaviour[J]. Géotechnique, 2003, 53(1): 123–135.
[5]	JOMMI C. Remarks on the constitutive modelling of unsaturated soils[C]// Proceedings of An International Workshop on Unsaturated Soils. Trento, 2000: 139–154.
[6]	WHEELER S J, SHARMA R S, BUISSON M S R. Coupling of hydraulic hysteresis and stress–strain behaviour in unsaturated soils[J]. Géotechnique, 2003, 53(1): 41–54.
[7]	孙德安. 饱和度对非饱和土力学性质的影响[J]. 岩土力学, 2009, 30(增刊2): 13–16. (SUN De-an. Effect of saturation degree on mechanical behaviours of unsaturated soils[J]. Rock and Soil Mechanics, 2009, 30(S2): 13–16. (in Chinese))
[8]	ZHAO C G, LIU Y. Work and energy equations and the principle of generalized effective stress for unsaturated soils[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 2010, 34(6): 920–936.
[9]	孙德安. 非饱和土的水力和力学特性及其弹塑性描述[J]. 岩土力学, 2009, 30(11): 3217–3231. (SUN De-an. Hydro-mechanical behaviours of unsaturated soils and their elastoplastic modeling[J]. Rock and Soil Mechanics, 2009, 30(11): 3217–3231. (in Chinese))
[10]	刘艳. 非饱和土的广义有效应力原理及其本构模型研究[D]. 北京: 北京交通大学, 2010. (LIU Yan. Study on the principle of generalized effective stress and constitutive modeling of unsaturated soils[D]. Beijing: Beijing Jiaotong University, 2010. (in Chinese))
[11]	CUNNINGHAM M R, RIDLEY A M, DINEEN K, et al. The mechanical behaviour of a reconstituted unsaturated silty clay[J]. Géotechnique, 2003, 53(2): 183–194.
[12]	VAN GENUCHTEN M T. A closed-form equation for predicting the hydraulic conductivity of unsaturated soil[J]. Soil Science Society of America Journal, 1980, 44: 892–898.

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非饱和土的修正SFG模型研究 English Version

作者简介: 刘 艳(1983– )，女，博士后，主要从事非饱和土力学方面的研究工作。

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出版历程

Modified SFG model for unsaturated soils

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出版历程

目录

作者简介:
刘艳(1983– )，女，博士后，主要从事非饱和土力学方面的研究工作。