Technical Papers
May 7, 2024

A Fully Coupled Numerical Framework for Predicting Dynamic Behavior in Unsaturated Soils and Its Application to Embankment Seismic Analysis

Publication: International Journal of Geomechanics
Volume 24, Issue 7

Abstract

A soil–water–air fully coupled numerical framework is proposed to predict the deformation and hydraulic behavior of soils under different saturation states in response to dynamic loading. The proposed framework is developed based on the mixture theory of porous media and the governing equations are discretized with the finite-element method. The soil behavior is modeled by a sophisticated constitutive model. The hysteresis characteristic and the mutual dependence between volume change and the degree of saturation in the soil–water characteristic curve (SWCC) are considered. A consistent description for both unsaturated and saturated soils is achieved by taking the effective stress and the degree of saturation as the two independent variables, with only one set of unified mechanical/hydraulic parameters. The numerical framework is first validated at the element level against undrained and unvented strain-controlled cyclic triaxial test results of unsaturated Toyoura sand. The reliability of the proposed framework in addressing boundary value problems is further validated by the simulation of a dynamic centrifuge model test. The numerical framework is further applied to the dynamic stability analysis of unsaturated embankments with different initial water contents. The results show that initially unsaturated embankments with relatively high water content are susceptible to liquefaction during seismic loading. There is a significant correlation between the liquefaction and the deformation-induced soil saturation. Deformation-induced saturation initially occurs at the toe of the embankment and then gradually extends to the areas near the lateral surfaces of the embankment, which triggers the development of shear bands.

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Data Availability Statement

All data, models, and code generated or used during the study appear in the published article.

Acknowledgments

The authors wish to acknowledge the financial support from the National Natural Science Foundation of China (Grant Nos. 41727802 and 42072317) and the Science and Technology Commission of Shanghai Municipality (Funding No. 21DZ1204300).

Notation

The following symbols are used in this paper:
bi
body force;
br
parameter of anisotropy;
c1
fitting parameter shaping the drying boundary curve;
c2
fitting parameter shaping the wetting boundary curve;
c3
fitting parameter shaping the scanning curve;
Dijkl
stiffness tensor;
Eijkl
stiffness tensor in Hooke’s law;
EijRFS
stiffness tensor related to the degree of saturation;
Eijklep
elastoplastic stiffness tensor;
e
void ratio;
f
yield surface;
κ
swelling index;
Kα
bulk modulus of water/air (α = w, a);
kα
intrinsic permeability of water/air (α = w, a);
ks1s
initial stiffness of the scanning curve;
M
stress ratio at the critical state;
m*
parameter related to structure;
m
parameter related to overconsolidation;
N
void ratio at NCL under reference state;
N(Sr)
void ratio at NCLS under reference state;
n
soil porosity;
p
mean stress on the subloading yield surface;
p¯
mean stress on the superloading yield surface;
p
mean stress on the normal yield surface;
p0
mean stress under the reference state;
pr
referenced mean stress;
Qi
interaction between the soil and air;
q
deviatoric stress on the subloading yield surface;
q¯
deviatoric stress on the superloading yield surface;
q
deviatoric stress on the normal yield surface;
q0
deviatoric stress under the reference state;
Ri
interaction between the soil and water;
Sij
deviatoric stress tensor;
Sr
degree of saturation;
Srr
residual degree of saturation;
Srs
saturated degree of saturation;
s
suction;
sd
SWCC parameter for the AEV on the drying boundary curve;
sw
SWCC parameter for the AEV on the wetting boundary curve;
ua
pore air pressure;
uw
pore water pressure;
V
integration domain in finite-element method;
v
Poisson’s ratio;
β
stress-induced anisotropic stress tensor;
δ
Kronecker’s delta;
η
stress ratio;
η~
stress tensor related to anisotropy;
λ
compression index;
ρ
average density of the mixture;
ρα
intrinsic density of soil/water/air (α = s, w, a);
ρ¯α
partial density of soil/water/air (α = s, w, a);
σij
total stress tensor;
σij
soil skeleton stress tensor; and
ζ
magnitude of anisotropy.

References

Akai, K., and T. Tamura. 1978. “Numerical analysis of multi-dimensional consolidation accompanied with elasto-plastic constitutive equation.” [In Japanese.] Proc. Jpn. Soc. Civ. Eng. 269: 95–104. https://doi.org/10.2208/jscej1969.1978.95.
Alonso, E. E., J.-M. Pereira, J. Vaunat, and S. Olivella. 2010. “A microstructurally based effective stress for unsaturated soils.” Géotechnique 60 (12): 913–925. https://doi.org/10.1680/geot.8.P.002.
Asaoka, A., M. Nakano, and T. Noda. 1998. “Super loading yield surface concept for the saturated structured soils.” In Application of numerical methods to geotechnical problems, edited by A. Cividini, 233–242. Vienna, Austria: Springer.
Borja, R. I. 2006. “On the mechanical energy and effective stress in saturated and unsaturated porous continua.” Int. J. Solids Struct. 43 (6): 1764–1786. https://doi.org/10.1016/j.ijsolstr.2005.04.045.
Cui, Y. J., and P. Delage. 1996. “Yielding and plastic behaviour of an unsaturated compacted silt.” Géotechnique 46 (2): 291–311. https://doi.org/10.1680/geot.1996.46.2.291.
Dang, K., K. Sassa, H. Fukuoka, N. Sakai, Y. Sato, K. Takara, L. H. Quang, D. H. Loi, P. Van Tien, and N. D. Ha. 2016. “Mechanism of two rapid and long-runout landslides in the 16 April 2016 kumamoto earthquake using a ring-shear apparatus and computer simulation (LS-RAPID).” Landslides 13 (6): 1525–1534. https://doi.org/10.1007/s10346-016-0748-9.
Fredlund, D. G., A. Xing, M. D. Fredlund, and S. L. Barbour. 1996. “The relationship of the unsaturated soil shear strength to the soil–water characteristic curve.” Can. Geotech. J. 33 (3): 440–448. https://doi.org/10.1139/t96-065.
Gallipoli, D., A. Gens, R. Sharma, and J. Vaunat. 2003. “An elasto-plastic model for unsaturated soil incorporating the effects of suction and degree of saturation on mechanical behaviour.” Géotechnique 53 (1): 123–135. https://doi.org/10.1680/geot.2003.53.1.123.
Ghorbani, J., D. W. Airey, and A. El-Zein. 2018. “Numerical framework for considering the dependency of SWCCs on volume changes and their hysteretic responses in modelling elasto-plastic response of unsaturated soils.” Comput. Methods Appl. Mech. Eng. 336: 80–110. https://doi.org/10.1016/j.cma.2018.03.008.
Hashiguchi, K., and M. Ueno. 1977. “Elastoplastic constitutive laws of granular materials, constitutive equations of soils.” In Proc., 9th ICFSME, Spec. Session 9, JSSMFE, 73–82. Tokyo, Japan: Japanese Society of Soil Mechanics and Foundation Engineering (JSSMFE).
Higo, Y., C.-W. Lee, T. Doi, T. Kinugawa, M. Kimura, S. Kimoto, and F. Oka. 2015. “Study of dynamic stability of unsaturated embankments with different water contents by centrifugal model tests.” Soils Found. 55 (1): 112–126. https://doi.org/10.1016/j.sandf.2014.12.009.
Khalili, N., E. Romero, and F. Marinho. 2022. “Advances in unsaturated soil mechanics: Constitutive modelling, experimental investigation, and field instrumentation.” In Proc., 20th Int. Conf. on Soil Mechanics and Geotechnical Engineering. Sydney, Australia: Australian Geomechanics Society.
Khoei, A. R., and T. Mohammadnejad. 2011. “Numerical modeling of multiphase fluid flow in deforming porous media: A comparison between two- and three-phase models for seismic analysis of earth and rockfill dams.” Comput. Geotech. 38 (2): 142–166. https://doi.org/10.1016/j.compgeo.2010.10.010.
Kohgo, Y., M. Nakano, and T. Miyazaki. 1993. “Theoretical aspects of constitutive modelling for unsaturated soils.” Soils Found. 33 (4): 49–63. https://doi.org/10.3208/sandf1972.33.4_49.
Kwa, K., and D. Airey. 2019. “Effects of fines on the cyclic liquefaction behaviour in unsaturated, well-graded materials.” Soils Found. 59 (4): 857–873. https://doi.org/10.1016/j.sandf.2019.03.001.
Likos, W. J., X. Song, M. Xiao, A. Cerato, and N. Lu. 2019. “Fundamental challenges in unsaturated soil mechanics.” In Geotechnical fundamentals for addressing new world challenges, edited by N. Lu and J. K. Mitchell, 209–236. Cham, Switzerland: Springer.
Loret, B., and N. Khalili. 2000. “A three-phase model for unsaturated soils.” Int. J. Numer. Anal. Methods Geomech. 24: 893–927. https://doi.org/10.1002/1096-9853(200009)24:11%3C893::AID-NAG105%3E3.0.CO;2-V.
Matsumaru, T., and R. Uzuoka. 2016. “Three-phase seepage-deformation coupled analysis about unsaturated embankment damaged by earthquake.” Int. J. Geomech. 16 (5): 4016006. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000699.
Okamura, M., and Y. Soga. 2006. “Effects of pore fluid compressibility on liquefaction resistance of partially saturated sand.” Soils Found. 46 (5): 695–700. https://doi.org/10.3208/sandf.46.695.
Ravichandran, N., and K. K. Muraleetharan. 2009. “Dynamics of unsaturated soils using various finite element formulations.” Int. J. Numer. Anal. Methods Geomech. 33 (5): 611–631. https://doi.org/10.1002/nag.737.
Schrefler, B. A., and R. Scotta. 2001. “A fully coupled dynamic model for two-phase fluid flow in deformable porous media.” Comput. Methods Appl. Mech. Eng. 190 (24–25): 3223–3246. https://doi.org/10.1016/S0045-7825(00)00390-X.
Shahbodagh, B., H. Sadeghi, S. Kimoto, and F. Oka. 2020. “Large deformation and failure analysis of river embankments subjected to seismic loading.” Acta Geotech. 15 (6): 1381–1408. https://doi.org/10.1007/s11440-019-00861-3.
Sheng, D.-C. 2011. “Review of fundamental principles in modelling unsaturated soil behaviour.” Comput. Geotech. 38 (6): 757–776. https://doi.org/10.1016/j.compgeo.2011.05.002.
Sheng, D., A. Gens, D. G. Fredlund, and S. W. Sloan. 2008. “Unsaturated soils: From constitutive modelling to numerical algorithms.” Comput. Geotech. 35 (6): 810–824. https://doi.org/10.1016/j.compgeo.2008.08.011.
Sheng, D., S. W. Sloan, and H. S. Yu. 2000. “Aspects of finite element implementation of critical state models.” Comput. Mech. 26 (2): 185–196. https://doi.org/10.1007/s004660000166.
Song, X., and N. Khalili. 2019. “A peridynamics model for strain localization analysis of geomaterials.” Int. J. Numer. Anal. Methods Geomech. 43 (1): 77–96. https://doi.org/10.1002/nag.2854.
Sun, D. A., D. C. Sheng, H. B. Cui, and S. W. Sloan. 2007. “A density-dependent elastoplastic hydro-mechanical model for unsaturated compacted soils.” Int. J. Numer. Anal. Methods Geomech. 31 (11): 1257–1279. https://doi.org/10.1002/nag.579.
Toll, D. G. 1990. “A framework for unsaturated soil behaviour.” Géotechnique 40 (1): 31–44. https://doi.org/10.1680/geot.1990.40.1.31.
Tsukamoto, Y. 2019. “Degree of saturation affecting liquefaction resistance and undrained shear strength of silty sands.” Soil Dyn. Earthquake Eng. 124: 365–373. https://doi.org/10.1016/j.soildyn.2018.04.041.
Ueda, K., K. Bai, and S. Iai. 2018. “Applicability of the simplified three-phase analysis to the seismic behavior of unsaturated laterally layered ground.” [In Japanese.] J. Jpn. Soc. Civ. Eng., Ser. C (Geosphere Eng.) 74 (2): 130–143. https://doi.org/10.2208/jscejge.74.130.
Unno, T., R. Uzuoka, N. Sento, and M. Kazama. 2013. “Pore air pressure effect on cyclic shear behavior of unsaturated sandy soil.” [In Japanese.] J. Jpn. Soc. Civ. Eng., Ser. C (Geosphere Eng.) 69 (3): 386–403. https://doi.org/10.2208/jscejge.69.386.
Uzuoka, R., T. Unno, T. Matsumaru, and K. Ueda. 2019. “Three-phase coupled seismic analyses of unsaturated/saturated grounds.” Jpn. Geotech. Soc. Spec. Publ. 7 (2): 38–45. https://doi.org/10.3208/jgssp.v07.005.
Vaunat, J., J. C. Cante, A. Ledesma, and A. Gens. 2000. “A stress point algorithm for an elastoplastic model in unsaturated soils.” Int. J. Plast. 16 (2): 121–141. https://doi.org/10.1016/S0749-6419(99)00033-9.
Wei, C., and K. K. Muraleetharan. 2002. “A continuum theory of porous media saturated by multiple immiscible fluids: I. Linear poroelasticity.” Int. J. Eng. Sci. 40 (16): 1807–1833. https://doi.org/10.1016/S0020-7225(02)00068-X.
Wheeler, S. J. 1996. “Inclusion of specific water volume within an elasto-plastic model for unsaturated soil.” Can. Geotech. J. 33 (1): 42–57. https://doi.org/10.1139/t96-023.
Xiong, Y.-l., G.-l. Ye, Y. Xie, B. Ye, S. Zhang, and F. Zhang. 2019. “A unified constitutive model for unsaturated soil under monotonic and cyclic loading.” Acta Geotech. 14 (2): 313–328. https://doi.org/10.1007/s11440-018-0754-2.
Ye, B., G. Ye, and F. Zhang. 2012. “Numerical modeling of changes in anisotropy during liquefaction using a generalized constitutive model.” Comput. Geotech. 42: 62–72. https://doi.org/10.1016/j.compgeo.2011.12.009.
Yoshikawa, T., T. Noda, T. Kodaka, and T. Takaine. 2016. “Analysis of the effect of groundwater level on the seismic behavior of an unsaturated embankment on clayey ground.” Soil Dyn. Earthquake Eng. 85: 217–230. https://doi.org/10.1016/j.soildyn.2016.02.008.
Zhang, B., and K. K. Muraleetharan. 2018. “Liquefaction of level ground unsaturated sand deposits using a validated fully coupled analysis procedure.” Int. J. Geomech. 18 (10): 04018118. https://doi.org/10.1061/(ASCE)GM.1943-5622.0001230.
Zhang, F., and T. Ikariya. 2011. “A new model for unsaturated soil using skeleton stress and degree of saturation as state variables.” Soils Found. 51 (1): 67–81. https://doi.org/10.3208/sandf.51.67.
Zhang, F., Y. Jin, and B. Ye. 2010. “A try to give a unified description of Toyoura sand.” Soils Found. 50 (5): 679–693. https://doi.org/10.3208/sandf.50.679.
Zhou, A.-N., D. Sheng, S. W. Sloan, and A. Gens. 2012. “Interpretation of unsaturated soil behaviour in the stress – saturation space, I: Volume change and water retention behaviour.” Comput. Geotech. 43: 178–187. https://doi.org/10.1016/j.compgeo.2012.04.010.
Zienkiewicz, O. C., Y. M. Xie, and B. A. Schrefler. 1990. “Static and dynamic behavior of soils: A rational approach to quantitative solutions. II. Semi-saturated problems.” Proc. R. Soc. London, Ser. A 429 (1877): 311–321.

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Go to International Journal of Geomechanics
International Journal of Geomechanics
Volume 24Issue 7July 2024

History

Received: Apr 24, 2023
Accepted: Jan 14, 2024
Published online: May 7, 2024
Published in print: Jul 1, 2024
Discussion open until: Oct 7, 2024

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State Key Laboratory of Ocean Engineering, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., Shanghai 200240, China. Email: [email protected]
Wenxuan Zhu [email protected]
State Key Laboratory of Ocean Engineering, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., Shanghai 200240, China. Email: [email protected]
Yonglin Xiong [email protected]
Institute of Geotechnical Engineering, Ningbo Univ., Ningbo 315211, China. Email: [email protected]
State Key Laboratory of Ocean Engineering, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., Shanghai 200240, China (corresponding author). ORCID: https://orcid.org/0000-0003-4097-3061. Email: [email protected]

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