基于SFG模型的非饱和沉积土本构模型

doi:10.12066/j.issn.1007-2861.1930

Abstract

Abstract:

The Sheng-Fredlund-Gens (SFG) model is modified by considering coupled water-retention and mechanical behavior to reflect the behavior of unsaturated sedimentary soils. The net stress is replaced with the average skeleton stress for stress state variable, and the influence of saturation on deformation is considered in the model. Based on test data of pre-consolidated clay at constant suctions for isotropic compression and triaxial shear, relationship between degree of saturation and void ratio is found, and the effect of deformation on saturation is considered in modeling the soil-water retention curve (SWRC). The loading collapse yield surface equation is derived from the volume change equation and SWRC equation. On the basis of a modified Cam-clay model, constitutive equations in triaxial stress state are derived with a unified hardening parameter that can describe shear contraction and dilatancy consistently. Using the same values of the model parameters, the hydraulic and mechanical behavior of unsaturated pre-consolidated clay can be consistently predicted under control of suction along isotropic compression and triaxial stress paths.

Key words: unsaturated soil, sedimentary soil, soil-water retention curve (SWRC), average skeleton stress, dilatancy

CLC Number:

TU43

ZHANG Zhao, SUN Dean, GAO You. Constitutive model for unsaturated sedimentary soils based on SFG model[J]. Journal of Shanghai University（Natural Science Edition）, 2019, 25(2): 337-346.

Add to citation manager EndNote|Reference Manager|ProCite|BibTeX|RefWorks

URL: https://www.journal.shu.edu.cn/EN/10.12066/j.issn.1007-2861.1930

https://www.journal.shu.edu.cn/EN/Y2019/V25/I2/337

Figures/Tables 7

Fig. 1

Fig. 2

Fig. 3

Table 1

Fig. 4

Fig. 5

Fig. 6

[1]	Alonso E E, Gens A, Josa A . A constitutive model for partially aturated soils[J]. Geotechnique, 1990,40(3):405-430. doi: 10.1099/00221287-40-3-405 pmid: 5864893
[2]	Kohgo Y, Nakano M, Miyazaki T . Theoretical aspects of constitutive modelling for unsaturated soils[J]. Soils and Foundations, 1993,33(4):49-63. doi: 10.3208/sandf1972.33.4_49
[3]	Gens A . Constitutive modelling: application to compacted soil [C]// Proceedings of the First International Conferonce on Unsaturated Soils. 1996: 1179-1200.
[4]	Wheeler S J, Karube D. State of the art report: constitutive modeling [C]// Proceedings of the first international conferonce on Unsaturated Soils. 1996: 1323-1356.
[5]	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. doi: 10.1680/geot.2003.53.1.41
[6]	Gallipoli D, Gens A, Sharma R , et al. An elastoplastic model for unsaturated soil incorporating the effects of suction and degree of aturation on mechanical behavior[J]. Geotechnique, 2003,53(1):123-135. doi: 10.1680/geot.2003.53.1.123
[7]	Sun D A, Sheng D C, Sloan S W . Elastoplastic modelling of hydraulic and tress-strain behaviour of unsaturated compacted soils[J]. Mechanics of Materials, 2007,39(3):212-221. doi: 10.1016/j.mechmat.2006.05.002
[8]	Hu R, Chen Y F, Liu H H , et al. A coupled stress-strain and hydraulic hysteresis model for unsaturated soils: thermodynamic analysis and model evaluation[J]. Computers and Geotechnics, 2015,63(1):159-170. doi: 10.1016/j.compgeo.2014.09.006
[9]	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(4):511-534. doi: 10.1139/T07-112
[10]	刘艳, 赵成刚, 韦昌富 . 非饱和土的修正SFG模型研究[J]. 岩土力学, 2012,34(8):1458-1463.
[11]	Yao Y P, Sun D A, Matsuoka H . A unified constitutive model for both clay and sand with hardening parameter independent on stress path[J]. Computers and Geotechnics, 2008,35(2):210-222. doi: 10.1016/j.compgeo.2007.04.003
[12]	Brooks R H.Corey A T. Hydraulic properties of porous media and their relation to drainage design[J]. Transaxtions of the ASAE, 1964,7:26-28.
[13]	Van Genuchten M T . A closed form equation for predicting the hydraulic conductivity of unsaturated soils[J]. Soil Science ociety of America Journal, 1980,44(2):892-898. doi: 10.1016/j.jconhyd.2006.05.001 pmid: 16797103
[14]	Fredlund D G, Xing A Q . Equation for soil-water characteristic curve[J]. Canadian Geotechnical Journal, 1994,31(4):521-532. doi: 10.1016/j.scitotenv.2019.134132 pmid: 31494428
[15]	Sun D A, Cui H B, Matsuoka H , et al. A three-dimensional elastoplastic model for unsaturated compacted soil with hysteresis[J]. Soils and Foundations, 2007,47(2):253-264. doi: 10.3208/sandf.47.253
[16]	Gao Y, Sun D A, Zhou A N . Hydro-mechanical behaviour of unsaturated soil with different specimen preparations[J]. Canadian Geotechnical Journal, 2016,53(6):909-917. doi: 10.1139/cgj-2015-0381

Constitutive model for unsaturated sedimentary soils based on SFG model

RichHTML

PDF

Knowledge

Abstract

Cite this article

share this article

Figures/Tables 7

Related Articles 15

Recommended Articles

Metrics

Comments

[1]	QIN Zhenyu, SUN De'an, ZHOU Xiangyun, LIU Yuemiao. Anisotropy of tensile strength of compacted Gaomiaozi bentonite [J]. Journal of Shanghai University（Natural Science Edition）, 2022, 28(4): 668-677.
[2]	QIN Aifang, XU Weifang, JIANG Lianghua. Analysis of radial consolidation of unsaturated soil with vertical drains considering drain resistance and the smear effect [J]. Journal of Shanghai University（Natural Science Edition）, 2021, 27(6): 1074-1084.
[3]	Dean SUN, Zhou ZHANG, You GAO, Bo CHEN. Determination of basic parameters of SWCC for clayer soils [J]. Journal of Shanghai University（Natural Science Edition）, 2019, 25(6): 957-964.
[4]	WANG Sicong, SUN Dean. Time effect of shear strengths of unsaturated fly-ash and its prediction [J]. Journal of Shanghai University（Natural Science Edition）, 2018, 24(1): 108-117.
[5]	QIN Aifang, Lü Kangli. Analysis of one-dimensional consolidation characteristics of viscoelastic unsaturated soils under cyclic loads [J]. Journal of Shanghai University（Natural Science Edition）, 2017, 23(6): 937-.
[6]	SUN Hongyun, SUN Dean. Shear strength of unsaturated Nanyang expansive soil and its prediction [J]. Journal of Shanghai University（Natural Science Edition）, 2017, 23(1): 121-127.
[7]	QIN Aifang, GE Hang. Analysis of one-dimensional consolidation characteristics in unsaturated soil under line loads [J]. Journal of Shanghai University（Natural Science Edition）, 2016, 22(5): 624-636.
[8]	JIA Lei, SUN De-an, HAO Fei. Dynamic deformation characteristics of unsaturated silt under suction control [J]. Journal of Shanghai University（Natural Science Edition）, 2015, 21(1): 117-127.
[9]	ZHANG Tian-feng, SUN De-an, LIU Wen-jie. Relationship between Shear Strength and Moisture Content for Guilin Laterite [J]. Journal of Shanghai University（Natural Science Edition）, 2014, 20(5): 586-595.
[10]	XU Zhi-liang, SUN De-an, ZHANG Jin-yi. Mechanical Behavior of Fly Ash and Its Elastoplastic Modeling [J]. Journal of Shanghai University（Natural Science Edition）, 2013, 19(1): 106-110.
[11]	SUN De-an, YANG Xian-cai. Experimental Study on Hydro-Mechanical Behavior of Unsaturated Silt [J]. Journal of Shanghai University（Natural Science Edition）, 2012, 18(6): 627-633.
[12]	CHEN Zhen-xin,SUN De-an. Soil-Water and Deformation Characteristics of Unsaturated Shanghai Soft Clays [J]. Journal of Shanghai University（Natural Science Edition）, 2012, 18(1): 98-103.
[13]	QIN Ai-Fang, YANG Liu-Ping, SUN De-An, JIANG Rui. One-Dimensional Consolidation Behavior of Unsaturated Soils under Two Boundary Conditions [J]. Journal of Shanghai University（Natural Science Edition）, 2011, 17(3): 314-319.
[14]	QIN Ai-Fang, LUO Kun, SUN De-An. Analysis of Consolidation Characteristic of One-Dimensional Visco-Elastic Consolidation for Unsaturated Soils [J]. Journal of Shanghai University（Natural Science Edition）, 2010, 16(2): 203-209.
[15]	SUN Wen-jing,SUN De-an,YAN Wei. Deformation Characteristics of Unsaturated Bentonite under K₀-Compression Stress State [J]. Journal of Shanghai University（Natural Science Edition）, 2010, 16(1): 105-110.