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Three-dimensional seismic stability analysis of slopes with linearly increasing undrained shear strength

  • Yunwei Shi (School of Ocean & Civil Engineering, Shanghai Jiao Tong University) ;
  • Xianqi Luo (School of Ocean & Civil Engineering, Shanghai Jiao Tong University) ;
  • Pingfan Wang (School of Ocean & Civil Engineering, Shanghai Jiao Tong University)
  • Received : 2025.01.07
  • Accepted : 2025.04.07
  • Published : 2025.05.25

Abstract

Undrained stability of slopes has long been of interest to the community of geotechnical engineering due to its practical importance. However, the role of the undrained shear strength cu in the seismic stability and failure geometry of slopes under three-dimensional (3D) condition has not been fully understood. Therefore, this study adopts a modified 3D rotational failure mechanism to develop the upper bound solution to the stability number Ns for slopes with linearly increasing cu with depth based on the kinematic approach of limit analysis. The seismic force is included using the pseudo-static method. Three types of failure mechanisms, i.e., the toe failure, face failure and below-toe failure are considered to capture the critical condition. Stability charts that cover a wide range of parameters and representative failure surfaces are then developed to illustrate the influence of key factors. Results show that the stability and failure geometry of slopes are significantly influenced by the variation ratio of cu with depth. The most significant outcome is that an increase in the horizontal seismic coefficient kh leads to a shallower critical failure surface when the slope with a large variation ratio of cu is constrained within a narrow width.

Keywords

Acknowledgement

The research described in this paper was financially supported by the National Natural Science Foundation of China (Project No..: 51208301). The authors wish to express their gratitude for the above financial support.

References

  1. Ajith, A., Francis, K.A. and Pillai, R.J. (2024), "Evaluation of pore-pressure variation and slope stability on terraced cultivation using physics-based landslide susceptibility model", Geomorphology., 450, 109081. https://doi.org/10.1016/j.geomorph.2024.109081.
  2. Azarafza, M., Bonab, M.H. and Akgun, H. (2021), "Numerical analysis and stability assessment of complex secondary toppling failures: A case study for the south pars special zone", Geomech. Eng., 27(5), 481-495. https://doi.org/10.12989/gae.2021.27.5.481.
  3. Bhandari, T., Hamad, F., Moormann, C., Sharmai, K.G. and Westrich, B. (2016), "Numerical modelling of seismic slope failure using MPM", Comput. Geotech., 75, 126-134. https://doi.org/10.1016/j.compgeo.2016.01.017.
  4. Bi, J.F., Luo, X.Q., Zhang, H.T. and Shen, H. (2019), "Stability analysis of complex rock slopes reinforced with prestressed anchor cables and anti-shear cavities", Bull. Eng. Geol. Environ., 78(2), 2027-2039. https://doi.org/10.1007/s10064-017-1171-8.
  5. Bonilla-Sierra, V., Scholtes, L., Donze, F.V. and Elmouttie, M.K. (2015), "Rock slope stability analysis using photogrammetric data and DFN–DEM modelling", Acta Geotech., 10(4), 497-511. https://doi.org/10.1007/s11440-015-0374-z.
  6. Chehade, H.A., Dias, D., Sadek, M., Jenck, O. and Chehade, F.H. (2022), "Seismic internal stability of saturated reinforced soil retaining walls using the upper bound theorem of limit analysis", Soil Dyn. Earthq. Eng., 155, 107180. https://doi.org/10.1016/j.soildyn.2022.107180.
  7. Chen, W.F. (1975), Limit Analysis and Soil Plasticity, Elsevier Scientific Publishing Company, New York, NY, USA.
  8. Chen, Z.Y. (1992), "Random trials used in determining global minimum factors of safety of slopes", Can. Geotech. J., 29(2), 225-233. https://doi. org/ 10. 1139/ t92- 026. https://doi.org/10.1139/t92-026
  9. Chaudhary, N., Metya, S. and Sharma, K.K. (2024), "Influence of hydraulic distribution pattern on the rock slope stability under block toppling failure", KSC J. Civ. Eng., 28(4), 1253-1266. https://doi.org/10.12989/gae.2019.19.2.179.
  10. Deng, D.P., Lu, K. and Li, L. (2019), "LE analysis on unsaturated slope stability with introduction of nonlinearity of soil strength", Geomech. Eng., 19(2), 179-191. https://doi.org/10.12989/gae.2019.19.2.179.
  11. Feng, Z.K. and Xu, W.J. (2021), "GPU material point method (MPM) and its application on slope stability analysis", Bull. Eng. Geol. Environ., 80(7), 5437-5449. https://doi.org/10.1007/s10064-021-02265-8.
  12. Gao, G., Meguid, M.A., Chouinard, L.E. and Zhan, W.W. (2021), "Dynamic disintegration processes accompanying transport of an earthquake-induced landslide", Landslides., 18(3), 909-933. https://doi.org/10.1007/s10346-020-01508-1.
  13. Gap, Y.F., Zhang, F., Lei, G.H., Li, D.Y., Wu, Y.X. and Zhang, N. (2013), "Stability charts for 3D failures of homogeneous slopes", J. Geotech. Geoenviron. Eng., 139(9), 1528-1538. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000866.
  14. Griffiths, D.V. and Yu, X. (2015), "Another look at the stability of slopes with linearly increasing undrained strength", Geotechnique, 65(10), 824-830. https://doi.org/10.1680/jgeot.14.T.030.
  15. Griffiths, D.V. and Martin, C.M. (2020), "Critical failure mechanisms in relatively flat undrained slopes", Geotech. Lett., 10(2), 95-99. https://doi.org/10.1680/jgele.19.00075.
  16. Hong-in, P., Keawsawasvong, S., Lai, V.Q., Nguyen, T.S., Tanapalungkorn, W. and Likitlersuang, S. (2023), "3D stability and failure mechanism of undrained clay slopes subjected to seismic load", Geotech. Geol. Eng., 41(7), 3941-3969. https://doi.org/10.1007/s10706-023-02497-3.
  17. Hossley, A. and Lenshchinsky, B. (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.
  18. Huang, A.P., Zhu, Y.P., Ye, S.H., Wang, L., Peng, J.G. and Fang, G.W. (2023), "Seismic stability limit analysis of unsaturated soil slopes reinforced by frame beam anchor plates", KSCE J. Civ. Eng., 27(9), 3778-3792. https://doi.org/10.1007/s12205-023-1928-5.
  19. Hunter, J.H. and Schuster, R.L. (1968), "Stability of simple cuttings in normally consolidated clays", Geotechnique, 18(3), 372-378. https://doi.org/10.1680/geot.1968.18.3.372.
  20. Karrech, A., Dong, X., Elchalakani, M., Basarir, H., Shahin, M.A. and Regenauer-Lieb, K. (2022), "Limit analysis for the seismic stability of three-dimensional rock slopes using the generalized Hoek-Brown criterion", Int. J. Min. Sci. Technol., 32(2), 237-245. https://doi.org/10.1016/j.ijmst.2021.10.005.
  21. Ke, L.J., Gao, Y.F., Zhao, Z.H., Zhou, Y.D. and Ji, J. (2021), "Undrained bearing capacity of strip footing near slopes considering the orientation of strength increase", Int. J. Geomech., 21(7), 06021016. https://doi.org/10.1061/(ASCE)GM.1943-5622.0002088.
  22. Koppula, S.D. (1984), "On stability of slopes in clays with linearly increasing strength", Can. Geotech. J., 21(3), 577-581. https://doi.org/10.1139/t84-059.
  23. Kumar, J., Chakraborty, M. and Sahoo, J.P. (2014), "Stability of unsupported vertical circular excavations", J. Geotech. Geoenviron. Eng., 140(7), 04014028. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001118.
  24. Li, A.J., Merifield, R.S. and Lyamin, A.V. (2009), "Limit analysis solutions for three dimensional undrained slopes", Comput. Geotech., 36(8), 1330-1351. https://doi.org/10.1016/j.compgeo.2009.06.002.
  25. Li, B., Zhang, F. and Wang, D. (2018), "Impact of crack on stability of slope with linearly increasing undrained strength", Math. Probl. Eng., 2018, 1096513. https://doi.org/10.1155/2018/1096513.
  26. Mase, L.Z., Likitlersuang, S. and Tobita, T. (2020), "Verification of liquefaction potential during the strong earthquake at the border of Thailand–Myanmar", J. Earthq. Eng., 26(4), 2023-2050. https://doi.org/10.1080/13632469.2020.1751346.
  27. Mase, L.Z., Likitlersuang, S. and Tobita, T. (2021), "Ground motion parameters and resonance effect during strong earthquake in northern Thailand", Geotech. Geol. Eng., 39(3), 2207-2210. https:// doi. org/ 10.1007/ s10706- 020- 01619-5.
  28. Mase, L.Z., Tanapalungkorn, W., Likitlersuang, S., Ueda, K. and Tobita, T. (2022), "Liquefaction analysis of Izumio sands under variation of ground motions during strong earthquake in Osaka", Soils Found., 62(5), 101218. https://doi.org/10.1016/j.sandf.2022.101218.
  29. Mase, L.Z., Tanapalungkorn, W., Anussornrajkit, P. and Likitlersuang, S. (2024), "Assessing liquefaction risk and hazard mapping in a high-seismic region: a case study of Bengkulu City, Indonesia", Nat. Hazards, Online. https://doi.org/10.1007/s11069-024-07057-3.
  30. Michalowski, R.L. (2002), "Stability charts for uniform slopes", J. Geotech. Geoenviron. Eng., 128(4), 351-355. https://doi.org/10.1061/(ASCE)1090-0241(2002)128:4(351).
  31. Michalowski, R.L. and Drescher, A. (2009), "Three-dimensional stability of slopes and excavations", Geotechnique, 59(10), 839-850. https://doi.org/10.1680/geot.8.P.136.
  32. Naeij, M., Ghasemi, H., Ghafarian, D. and Javanmardi, Y. (2021), "Explicit finite element analysis of slope stability by strength reduction", Geomech. Eng., 26(2), 133-146. https://doi.org/10.12989/gae.2021.26.2.133.
  33. Petchkaew, P., Keawsawasvong, S., Tanapalungkorn, W. and Likitlersuang, S. (2023a), "3D stability analysis of unsupported rectangular excavation under pseudo-static seismic body force", Geomech. Geoeng., 18(3), 175-192. https://doi.org/10.1080/17486025.2021.2019321.
  34. Petchkaew, P., Keawsawasvong, S., Tanapalungkorn, W. and Likitlersuang, S. (2023b), "Seismic stability of unsupported vertical circular excavations in c‑φ soil", Transp. Infrastruct. Geotechnol., 10(2), 165-179. https://doi.org/10.1007/s40515-021-00221-3.
  35. Qin, C.B., Chian, S.C. and Yu, J. (2018), "Stability analysis of initial collapse and earthquake-induced secondary failure using discretization-based kinematic analysis", Int. J. Gemech., 18(11), 04018155. https://doi.org/10.1061/(ASCE)GM.1943-5622.0001304.
  36. Park, D. and Michalowski, R.L. (2018), "Intricacies in threedimensional limit analysis of earth slopes", Int. J. Numer. Anal. Methods Geomech., 42(17), 2109-2129. https://doi.org/10.1002/nag.2846.
  37. Rao, P.P., Wu, J., Jiang, G.Y., Shi, Y.W., Chen, Q.S. and Nimbalkar, S. (2021), "Seismic stability analysis for a two-stage slope", Geomech. Eng., 27(2), 189-196. https://doi.org/10.12989/gae.2021.27.2.189.
  38. Ray, R., Deb, K. and Shaw, A. (2019), "Pseudo-Spring smoothed part icle hydrodynamics (SPH) based computational model for slope failure", Eng. Anal. Bound. Elem., 101, 139-148. https://doi.org/10.1016/j.enganabound.2019.01.005.
  39. Satyanaga, A., Moon, S.W. and Kim, J.R. (2022), "Stability analyses of dual porosity soil slope", Geomech. Eng., 28(1), 77-87. https://doi.org/10.12989/gae.2021.28.1.077.
  40. Shi, Y.W., Luo, X.Q. and Wang, P.F. (2022), "Three-dimensional stability assessment of slopes with spatially varying undrained shear strength", Geomech. Eng., 31(4), 375-384. https://doi.org/10.12989/gae.2022.31.4.375.
  41. Shu, S., Ge, B., Wu, Y.X. and Zhang, F. (2023), "Probabilistic assessment on 3D stability and failure mechanism of undrained slopes based on the kinematic approach of limit analysis", Int. J. Geomech., 23(1), 06022037. https://doi.org/10.1061/(ASCE)GM.1943-5622.0002635.
  42. Tran, A.T.P., Kim, A.R. and Cho, G.C. (2019), "Numerical modeling on the stability of slope with foundation during rainfall", Geomech. Eng., 17(1), 109-118. https://doi.org/10.12989/gae.2019.17.1.109.
  43. Tran, A.T.P., Cho, Y., Seo, H. and Kim, B. (2023), "Seismic fragility assessments of fill slopes in South Korea using finite element simulations", Geomech. Eng., 32(4), 341-380. https://doi.org/10.12989/gae.2023.34.4.341.
  44. Ukritchon, B., Yoang, S. and Keawsawasvong, S. (2020), "Undrained stability of unsupported rectangular excavations in non-homogeneous clays", Comput. Geotech., 117, 103281. https://doi.org/10.1016/j.compgeo.2019.103281.
  45. Wang, L., Sun, D.A. and Li, L. (2019), "3D stability of partially saturated soil slopes after rapid drawdown by a new layer-wise summation method", Landslides., 16(2), 295-313. https://doi.org/10.1007/s10346-018-1081-2.
  46. Wang, Y.K., Shang, H.W., Wan, Y.K. and Yu, X. (2024), "Reliability analysis of soil slope reinforced by micro-pile considering spatial variability of soil strength parameters", Geomech. Eng., 36(6), 631-640. https://doi.org/10.12989/gae.2024.36.6.631.
  47. Wang, J.H. and Xu, WJ. (2025), "Slope stability and failure dynamics of rainfall-induced landslide: Algorithm and applications", Gomput. Geotech., 177, 106919. https://doi.org/10.1016/j.compgeo.2024.106919.
  48. Weng, M.C., Lin, M.L., Lo, C.M., Li, H.H., Lin, C.H., Lu, J.H. and Tsai, S.J. (2019), "Evaluating failure mechanisms of dip slope using a multiscale investigation and discrete element modelling", Eng. Geol., 263, 105303. https://doi.org/10.1016/j.enggeo.2019.105303.
  49. Yang, X.L. and Li, Z.W. (2018), "Comparison of factors of safety using a 3D failure mechanism with kinematic approach", Int. J. Geomech., 18(9), 04018107. https://doi.org/10.1061/(ASCE)GM.1943-5622.0001235.
  50. Yang, X.L. and Pan, Q.J. (2015), "Three dimensional seismic andstatic stability of rock slopes", Geomech. Eng., 18(1), 97-111. https://doi.org/10.12989/gae.2015.8.1.097.
  51. Zhang, F., Leshchinsky, D., Baker, R., Gao, Y.F. and Leshchinsky, B. (2016), "Implications of variationally derived 3D failure mechanism", Int. J. Numer. Anal. Method. Geomech., 40(18), 2514-2531. https://doi.org/ 10.1002/nag.2543.
  52. Zhang, X.Q., Song, X., Wu, S.C. and Zhong, G. (2024), "Meshless analysis method for the whole process of progressive failure of slope", Indian Geotech. J., 54(2), 500-513. https://doi.org/10.1007/s40098-023-00787-4.
  53. Zhou, Y., Zhang, F. and Li, B. (2019), "Static and seismic stability charts for three-dimensional cut slopes and natural slopes under short-term undrained conditions", Adv. Civ. Eng., 2019, 191467. https://doi.org/10.1155/2019/1914674.
  54. Zhou, J.F and Qin, C.B. (2020), "A novel procedure for 3D slope stability analysis: lower bound limit analysis coupled with block element method", Bull. Eng. Geol. Environ., 79(4), 1815-1829. https://doi.org/10.1007/s10064-019-01657-1.