Undrained Bearing Capacity of Strip Footing near Slopes Considering the Orientation of Strength Increase
Publication: International Journal of Geomechanics
Volume 21, Issue 7
Abstract
The effect of undrained shear strength profile is an important practical consideration for estimating the bearing capacity of a strip footing placed near slopes or excavations. Previous studies generally assume that the soil strength (cu) is uniform or increases linearly with depth but does not vary in a horizontal direction. However, the horizontal variation in soil strength is also commonly found in practice, which is usually caused by various depositional and postdepositional factors. A modified formulation of shear strength profile was defined to characterize this strength variation and was embedded in upper and lower bound finite-element limit analysis (FELA). Seven principal failure modes were revealed and discussed. A comprehensive parametric study was performed to assess the bearing capacity and failure mechanism accounting for the orientation of strength increase. It was found that strength variation in horizontal direction significantly influences the bearing capacity and its associated failure mode. Some novel variation trends of the bearing capacity and the rotation of strip footings were found as well.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This work was supported by the National Natural Science Foundation of China (Grant Nos. 51890912 and 51879091), the Fundamental Research Funds for the Central Universities (Grant No. B200203094), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No. KYCX20_0449).
References
Bjerrum, L. 1967. “Engineering geology of Norwegian normally consolidated marine clays as related to settlements of buildings.” Geotechnique 17 (2): 83–118. https://doi.org/10.1680/geot.1967.17.2.83.
Blatz, J. A., and R. J. Bathurst. 2003. “Limit equilibrium analysis of large-scale reinforced and unreinforced embankments loaded by a strip footing.” Can. Geotech. J. 40 (6): 1084–1092. https://doi.org/10.1139/t03-053.
Butterfield, R. 1999. “Dimensional analysis for geotechnical engineers.” Geotechnique 49 (3): 357–366. https://doi.org/10.1680/geot.1999.49.3.357.
Castelli, F., and E. Motta. 2010. “Bearing capacity of strip footings near slopes.” Geotech. Geol. Eng. 28 (2): 187–198. https://doi.org/10.1007/s10706-009-9277-9.
Chakraborty, D., and J. Kumar. 2015. “Seismic bearing capacity of shallow embedded foundations on a sloping ground surface.” Int. J. Geomech. 15 (1): 04014035. https://doi.org/10.1061/(asce)gm.1943-5622.0000403.
Chen, T., and S. Xiao. 2020. “An upper bound solution to undrained bearing capacity of rigid strip footings near slopes.” Int. J. Civ. Eng. 18: 475–485. https://doi.org/10.1007/s40999-019-00463-w.
Choudhury, D., and K. S. Subba Rao. 2006. “Seismic bearing capacity of shallow strip footings embedded in slope.” Int. J. Geomech. 6 (3): 176–184. https://doi.org/10.1061/(asce)1532-3641(2006)6:3(176).
Cinicioglu, O., and A. Erkli. 2018. “Seismic bearing capacity of surficial foundations on sloping cohesive ground.” Soil Dyn. Earthquake Eng. 111: 53–64. https://doi.org/10.1016/J.SOILDYN.2018.04.027.
Davis, E. H., and J. R. Booker. 1973. “Some adaptations of classical plasticity theory for soil stability problems.” In Proc. Symp. Role of Plasticity in Soil Mechanics, 24–41. Cambridge, UK: Cambridge University Press.
Ganesh, R., and J. P. Sahoo. 2020. “Coupled bearing capacity factor for strip foundations on cohesive-frictional soil slopes under static and seismic conditions.” Int. J. Geomech. 20 (11): 04020202. https://doi.org/10.1061/(ASCE)GM.1943-5622.0001851.
Georgiadis, K. 2010a. “Undrained bearing capacity of strip footings on slopes.” J. Geotech. Geoenviron. Eng. 136 (5): 677–685. https://doi.org/10.1061/(asce)gt.1943-5606.0000269.
Georgiadis, K. 2010b. “An upper-bound solution for the undrained bearing capacity of strip footings at the top of a slope.” Geotechnique 60 (10): 801–806. https://doi.org/10.1680/geot.09.T.016.
Georgiadis, K. 2010c. “The influence of load inclination on the undrained bearing capacity of strip footings on slopes.” Comput. Geotech. 37: 311–322. https://doi.org/10.1016/J.COMPGEO.2009.11.004.
Graham, J., M. Andrews, and D. Shields. 1988. “Stress characteristics for shallow footings in cohesionless slopes.” Can. Geotech. J. 25 (2): 238–249. https://doi.org/10.1016/0148-9062(89)90802-4.
Griffiths, D. V., and G. A. Fenton. 2004. “Probabilistic slope stability analysis by finite elements.” J. Geotech. Geoenviron. Eng. 130 (5): 507–518. https://doi.org/https://doi.org10.1061/(asce)1090-0241(2004)130:5(507).
Griffiths, D. V., and P. A. Lane. 1999. “Slope stability analysis by finite elements.” Geotechnique 49 (3): 387–403. https://doi.org/10.1680/geot.1999.49.3.387.
Gullà, G., M. C. Mandaglio, and N. Moraci. 2006. “Effect of weathering on the compressibility and shear strength of a natural clay.” Can. Geotech. J. 43 (6): 618–625. https://doi.org/10.1139/t06-028.
Hossley, A., and B. Leshchinsky. 2019. “Stability and failure geometry of slopes with spatially varying undrained shear strength.” J. Geotech. Geoenviron. Eng. 145 (5): 06019002. https://doi.org/10.1061/(asce)gt.1943-5606.0002046.
Javankhoshdel, S., and R. J. Bathurst. 2014. “Simplified probabilistic slope stability design charts for cohesive and cohesive-frictional (c–ϕ) soils.” Can. Geotech. J. 51 (9): 1033–1045. https://doi.org/10.1139/cgj-2013-0385.
Javankhoshdel, S., and R. J. Bathurst. 2016. “Influence of cross correlation between soil parameters on probability of failure of simple cohesive and c–ϕ slopes.” Can. Geotech. J. 53 (5): 839–853. https://doi.org/10.1139/cgj-2015-0109.
Jefferies, M. G., J. H. A. Crooks, D. E. Becker, and P. R. Hill. 1987. “Independence of geostatic stress from overconsolidation in some Beaufort Sea clays.” Can. Geotech. J. 24 (3): 342–356. https://doi.org/10.1139/t87-045.
Ji, J., W. Zhang, F. Zhang, Y. Gao, and Q. Lü. 2019. “Reliability analysis on permanent displacement of earth slopes using the simplified bishop method.” Comput. Geotech. 111: 22–29. https://doi.org/10.1016/j.compgeo.2019.02.027.
Jin, L., Y. Feng, H. Zhang, and Q. Feng. 2020. “The use of improved radial movement optimization to calculate the ultimate bearing capacity of a nonhomogeneous clay foundation adjacent to slopes.” Comput. Geotech. 118: 103338. https://doi.org/10.1016/j.compgeo.2019.103338.
Ke, L., Y. Gao, Y. Gu, and J. Ji. 2020. “Undrained bearing capacity of skids/pedrails during trenching for buried submarine pipelines.” Comput. Geotech. 119: 103362. https://doi.org/10.1016/j.compgeo.2019.103362.
Ke, L., Y. Gao, D. Li, J. Zhang, and J. Ji. 2019. “Undrained stability analysis of trenches for buried submarine pipelines.” Mar. Georesour. Geotechnol. 38 (5): 583–594. https://doi.org/10.1080/1064119X.2019.1604918.
Keawsawasvong, S., and B. Ukritchon. 2017. “Stability of unsupported conical excavations in non-homogeneous clays.” Comput. Geotech. 81: 125–136. https://doi.org/10.1016/j.compgeo.2016.08.007.
Keshavarz, A., M. Beygi, and R. Vali. 2019. “Undrained seismic bearing capacity of strip footing placed on homogeneous and heterogeneous soil slopes by finite element limit analysis.” Comput. Geotech. 113: 103094. https://doi.org/10.1016/j.compgeo.2019.103094.
Koppula, S. D. 1984. “On stability of slopes in clay with linearly increasing strength.” Can. Geotech. J. 21 (3): 577–581. https://doi.org/10.1139/t85-057.
Leshchinsky, B., and Y. Xie. 2016. “Bearing capacity for spread footings placed near c′–φ′ slopes.” J. Geotech. Geoenviron. Eng. 143 (1): 06016020. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001578.
Li, C., and P. Jiang. 2019. “Ultimate load of nonhomogeneous slopes determined by using the method of characteristics.” Eng. Geol. 105281. https://doi.org/10.1016/j.enggeo.2019.105281.
Li, C., A. Zhou, and P. Jiang. 2020. “Eccentric bearing capacity of embedded strip footings placed on slopes.” Comput. Geotech. 119: 103352. https://doi.org/10.1016/j.compgeo.2019.103352.
Lu, N., and J. Godt. 2008. “Infinite slope stability under steady unsaturated seepage conditions.” Water Resour. Res. 44 (11): 1–13. https://doi.org/10.1029/2008WR006976.
Luo, N., and R. J. Bathurst. 2017. “Reliability bearing capacity analysis of footings on cohesive soil slopes using RFEM.” Comput. Geotech. 89: 203–212. https://doi.org/10.1016/j.compgeo.2017.04.013.
Luo, N., and R. J. Bathurst. 2018. “Deterministic and random FEM analysis of full-scale unreinforced and reinforced embankments.” Geosynth. Int. 25 (2): 164–179. https://doi.org/10.1680/jgein.17.00040.
Lyamin, A. V., and S. W. Sloan. 2002a. “Lower bound limit analysis using non-linear programming.” Int. J. Numer. Methods Eng. 55: 573–611. https://doi.org/10.1002/nme.511.
Lyamin, A. V., and S. W. Sloan. 2002b. “Upper bound limit analysis using linear finite elements and non-linear programming.” Int. J. Numer. Methods Eng. 26: 181–216. https://doi.org/10.1002/nag.198.
Mesri, G., and M. Shahien. 2003. “Residual shear strength mobilized in first-time slope failures.” J. Geotech. Geoenviron. Eng. 129 (1): 12–31. https://doi.org/10.1061/(ASCE)1090-0241(2003)129:1(12).
Meyerhof, G. G. 1957. “The ultimate bearing capacity of foundations on slopes.” In Vol. 3 of Proc., 4th Int. Conf. on Soil Mechanics and Foundation Engineering, 384–386. London: Butterworths.
Optum G2. 2019. Finite element program for geotechnical analysis. Optum Computer Engineering. https://optumce.com/products/brochure-and-datasheet/.
Pantelidis, L., and D. V. Griffiths. 2015. “Footing on the crest of slope: Slope stability or bearing capacity?” Eng. Geol. Soc. Territory 2: 1231–1234. https://doi.org/10.1007/978-3-319-09057-3_215.
Rahardjo, H., T. T. Lim, M. F. Chang, and D. G. Fredlund. 1995. “Shear strength characteristics of a residual soil.” Can. Geotech. J. 32 (1): 60–77. https://doi.org/10.1139/t95-005.
Raj, D., Y. Singh, and S. K. Shukla. 2018. “Seismic bearing capacity of strip foundation embedded in c–ϕ soil slope.” Int. J. Geomech. 18 (7): 04018076. https://doi.org/10.1061/(asce)gm.1943-5622.0001194.
Saran, S., V. K. Sud, and S. C. Handa. 1989. “Bearing capacity of footings adjacent to slopes.” J. Geotech. Eng. 115 (4): 553–573. https://doi.org/10.1061/(ASCE)0733-9410(1989)115:4(553).
Shiau, J. S., R. S. Merifield, A. V. Lyamin, and S. W. Sloan. 2011. “Undrained stability of footings on slopes.” Int. J. Geomech. 11 (5): 381–390. https://doi.org/10.1061/(asce)gm.1943-5622.0000092.
Shields, D., N. Chandler, and J. Garnier. 1990. “Bearing capacity of foundations in slopes.” J. Geotech. Eng. 116 (3): 528–537. https://doi.org/10.1061/(ASCE)0733-9410(1990)116:3(528).
Skempton, A. W., R. L. Schuster, and D. J. Petley. 1969. “Joints and fissures in the London Clay at Wraysbury and Edgware.” Geotechnique 19 (2): 205–217. https://doi.org/10.1680/geot.1969.19.2.205.
Terzaghi, K. 1943. Theoretical soil mechanics. New York: Wiley.
Vesic, A. S. 1973. “Analysis of ultimate loads of shallow foundations.” J. Soil Mech. Found. Div. 99 (1): 45–73. https://doi.org/10.1061/JSFEAQ.0001846.
Wu, G., H. Zhao, M. Zhao, and Y. Xiao. 2020a. “Undrained seismic bearing capacity of strip footings lying on two-layered slopes.” Comput. Geotech. 122: 103539. https://doi.org/10.1016/j.compgeo.2020.103539.
Wu, G., R. Zhang, M. Zhao, and S. Zhou. 2020b. “Undrained stability analysis of eccentrically loaded strip footing lying on layered slope by finite element limit analysis.” Comput. Geotech. 123: 103600. https://doi.org/10.1016/j.compgeo.2020.103600.
Wu, Y., Y. Gao, L. Zhang, and J. Yang. 2019. “How the distribution characteristics of soil property affect probabilistic foundation settlement: From the view of the first four statistical moments.” Can. Geotech. J. 57: 595–607. https://doi.org/10.1139/cgj-2019-0089.
Xiao, Y., M. Zhao, R. Zhang, H. Zhao, and G. Wu. 2019. “Undrained bearing capacity of strip footings placed adjacent to two-layered slopes.” Int. J. Geomech. 19 (8): 06019014. https://doi.org/10.1061/(asce)gm.1943-5622.0001480.
Yang, S., B. Leshchinsky, K. Cui, F. Zhang, and Y. Gao. 2019. “Unified approach toward evaluating bearing capacity of shallow foundations near slopes.” J. Geotech. Geoenviron. Eng. 145 (12): 04019110. https://doi.org/10.1061/(asce)gt.1943-5606.0002178.
Yang, S., B. Leshchinsky, K. Cui, F. Zhang, and Y. Gao. 2020. “Influence of failure mechanism on seismic bearing capacity factors for shallow foundations near slopes.” Geotechnique 1–46. https://doi.org/10.1680/jgeot.19.p.329.
Zhang, R., Y. Xiao, M. Zhao, and J. Jiang. 2020. “Seismic bearing capacity of strip footings placed near c–φ soil slopes.” Soil Dyn. Earthquake Eng. 136: 106221. https://doi.org/10.1016/j.soildyn.2020.106221.
Zhou, H., G. Zheng, X. Yin, R. Jia, and X. Yang. 2017. “The bearing capacity and failure mechanism of a vertically loaded strip footing placed on the top of slopes.” Comput. Geotech. 94: 12–21. https://doi.org/10.1016/j.compgeo.2017.08.009.
Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 21 • Issue 7 • July 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Sep 13, 2020
Accepted: Mar 3, 2021
Published online: May 5, 2021
Published in print: Jul 1, 2021
Discussion open until: Oct 5, 2021
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.
Cited by
- Haizuo Zhou, Yipeng Shi, Xiaoxuan Yu, Huajun Xu, Gang Zheng, Shangchuan Yang, Yi He, Failure Mechanism and Bearing Capacity of Rigid Footings Placed on Top of Cohesive Soil Slopes in Spatially Random Soil, International Journal of Geomechanics, 10.1061/IJGNAI.GMENG-8306, 23, 8, (2023).
- Mohammad Shamsi, Mohammad Javad Shabani, Amir Hossein Vakili, Three-Dimensional Seismic Nonlinear Analysis of Topography–Structure–Soil–Structure Interaction for Buildings near Slopes, International Journal of Geomechanics, 10.1061/(ASCE)GM.1943-5622.0002301, 22, 3, (2022).
- Z Zhao, H Zhang, F Wu, Development of lateral capacity-based envelopes of twin-pile group under combined V–H–M loading, IOP Conference Series: Earth and Environmental Science, 10.1088/1755-1315/861/3/032061, 861, 3, (032061), (2021).