Combined Effect of Rainfall and Shear Strength on the Stability of Highway Embankments Made of Yazoo Clay in Mississippi

  • Masoud NobaharEmail author
  • Mohammad Sadik Khan
  • John Ivoke
Original Paper


Shallow slope failure repeatedly occurs in many highway slopes in Mississippi due to the abundance of expansive Yazoo Clay. The highly plastic clay soil undergoes repetitive wet–dry cycles, which reduces the shear strength to fully soften state. The current study focused on the progressive change in shear strength and the safety factor of slopes constructed out of Yazoo Clay. Undisturbed and remolded specimens were used to determine the peak, fully softened and residual shear strength, with effective normal stresses of 25, 50, and 100 kPa. The variations in shear strength were investigated with the 2D slope stability analysis software, which uses the Finite Element Method, Plaxis 2D. A highway slope in Jackson, MS was considered as the reference slope. Different rainfall volumes, 70.8 mm (2.78 in.) to 312.4 mm (12.29 in.), with a rainfall duration (30 min–7 days) based on 100-year return periods of Jackson, MS were utilized. Furthermore, three slope ratios 2H:1V, 3H:1V and, 4H:1V were selected for this study. The safety factor of the slope was determined based on peak shear strength soil test data. Later, the topsoil layer, which gets weathered within the active zone due to the repeated wet–dry cycle, was varied to fully softened and residual shear strengths. The slope stability analysis results showed that the safety factor reduces progressively from peak to residual shear strength. In addition, the factor of safety was critical when the soil reached its fully softened shear strength for 2H:1V and 3H:1V slopes with progressive rainfall. On the other hand, the 4H:1V slope reached failure at the residual phase with the presence of rainfall.


Progressive change in shear strength Factor of safety Fully softened shear strength Wet–dry cycle Yazoo clay Finite element method 



The studies described in this paper are based on the work supported by the Mississippi Department of Transportation’s (MDOT) State Study 286. The findings, conclusions, and recommendations expressed in this material are those of the authors and, necessarily, it does not reflect the viewpoints of the MDOT.


  1. Alonso E, Gens A, Lloret A, Delahaye C (1995) Effect of rain infiltration on the stability of slopes. In: Proceedings of the first international conference on unsaturated soils, UNSAT’95, Paris, France, vol 1, pp 241–249Google Scholar
  2. ASTM (1994) Standard test method for liquid limit, plastic limit and plasticity index of soils. ASTM Designation: D4318-93, American Society for Testing and Materials, West ConshohokenGoogle Scholar
  3. Au SWC (1998) Rain-induced slope instability in Hong Kong. Eng Geol 51(1):1–36CrossRefGoogle Scholar
  4. Brand EW (1984) Landslides in Southeast Asia: A state-of-art report. In: Proceedings of the 4th international symposium on landslides. Canadian Geotechnical Society, Toronto, pp 17–59Google Scholar
  5. Calvello M, Cascini L, Sorbino G (2008) A numerical procedure for predicting rainfall-induced movements of active landslides along pre-existing slip surfaces. Int J Numer Anal Meth Geomech 32(4):327–351CrossRefGoogle Scholar
  6. Chabrillat S, Goetz AF, Krosley L, Olsen HW (2002) Use of hyperspectral images in the identification and mapping of expansive clay soils and the role of spatial resolution. Remote Sens Environ 82(2):431–445CrossRefGoogle Scholar
  7. Clark GM (1987) Dehris slide and debris flow historical events in the Appalachians south of the glacial horder. In: Costa JE, Wieczorek GF (eds) Reviews in engineering geology, volume VII-debris flows/avalanches: process, recognition and mitigation. Geological Society of America, Boulder, pp 125–138CrossRefGoogle Scholar
  8. Crosta GB (2001) Failure and flow development of a complex slide: the 1993 Sesa landslide. Eng Geol 59(1–2):173–199CrossRefGoogle Scholar
  9. Das BM (2013) Advanced soil mechanics. CRC Press, Boca RatonGoogle Scholar
  10. Day RW, Axten GW (1989) Surficial stability of compacted clay slopes. J Geophys Eng 115(4):577–580.fGoogle Scholar
  11. de Campos LEP, Menezes MSS (1991) ‘A proposed procedure for slope stability analysis in tropical soils. In: Proceeding of the 6th international symposium on landslides, Christchurch, New Zealand, Balkema, Rotterdam, The Netherlands, vol 2, 1351–1355Google Scholar
  12. de Campos MP, Andrade MHN, Vargas EA Jr (1992) Unsaturated colluvium over rock slide in a forested site in Rio de Janeiro. Brazil. In: Proceedings of the 6th international symposium on landslides. A. A. Balkema, Brookfield, pp 1357–1364Google Scholar
  13. Dietrich WE, Reiss R, Hsu M, Montgomery DR (1995) A process-based model for colluvial soil depth and shallow land sliding using digital elevation data. Hydrol Process. 9:383–400CrossRefGoogle Scholar
  14. Dockery DT (2005) Engineering geologic failures and cost overruns: examples from Mississippi. In: Geological Society of America, Southeastern Section, 54th annual meeting, abstracts with programs 37(2)Google Scholar
  15. Douglas SC, Dunlap GT (2000) Light commercial construction on Yazoo clay. In: Proceeding of the 2nd Forensic Congress, ASCE, Reston. Edition. PTI Manual, Phoenix, pp 607–616Google Scholar
  16. Ellen SD, Fleming RW (1987) Mobilization of debris flows from soil slips. San Francisco Bay region, California. In: Costa JE, Wieczorek GF (eds) Reviews in engineering geology, volume VII-debris flows/avalanches: process. Recognition, and mitigation. Geological Society of America. Boulder, pp 31–40CrossRefGoogle Scholar
  17. Eschner AR, Patric JH (1982) Dehris avalanches in eastern upland forests. J For HO(o):343–347Google Scholar
  18. Eyles GO (1985) The New Zealand land resource inventory erosion classification. Water and Soil Misc. Publication No. 85, Soil Conservation Ctr., Aokautere, Ministry of Works and Development, WellingtonGoogle Scholar
  19. Fannin RJ, Jaakkola J (1999) Hydrological response of hillslope soils above a debris-slide head scarp. Can Geotech J 36(6):1111–1122CrossRefGoogle Scholar
  20. Fourie AB (1996) Predicting rainfall-induced slope instability. Proc Inst Civ Eng Geotech Eng 119(4):211–218CrossRefGoogle Scholar
  21. Fredlund DG, Rahardjo H (1993) Soil mechanics for unsaturated soils. Wiley, HobokenCrossRefGoogle Scholar
  22. Guzzetti F, Peruccacci S, Rossi M, Stark CP (2007) Rainfall thresholds for the initiation of landslides in central and southern Europe. Meteorol Atmos Phys 98(3–4):239–267CrossRefGoogle Scholar
  23. Hensen EJ, Smit B (2002) Why clays swell. J Phys Chem 106(49):12664–12667CrossRefGoogle Scholar
  24. Hossain J, Hossain MS, Hoyos LR (2013) Effect of rainfall on stability of unsaturated earth slope constructed on expansive clay. Geocongress. American Society of Civil Engineers, San DiegoCrossRefGoogle Scholar
  25. Johnson KA, Sitar N (1990) Hydrologic conditions leading to debris-flow initiation. Can Geotech J 27:789–801CrossRefGoogle Scholar
  26. Kayyal MK, Wright SG (1991) Investigation of long-term strength properties of paris and beaumont clays in earth embankments. Center for Transportation Research, Research Report 1195-2FGoogle Scholar
  27. Khan MS, Ivoke J, Nobahar M (2019) Coupled effect of wet-dry cycles and rainfall on highway slope made of Yazoo Clay. Geosciences, Open Access Journal by MDPI, ISSN 2076-3263, Manuscript ID 504447, April 28th, 9(8):341. CrossRefGoogle Scholar
  28. Kim J, Jeong S, Park S, Sharma J (2004) Influence of rainfall-induced wetting on the stability of slopes in weathered soils. Eng Geol 75(3–4):251–262CrossRefGoogle Scholar
  29. Lee Jr, Landris T (2012) State study 151 and 236: Yazoo Clay investigation. MDOT State Study 236, US Army Corps of EngineersGoogle Scholar
  30. National Oceanic and Atmospheric Administration Daily Climate Report (2014) Accessed 21 Apr 2017
  31. National Oceanic and Atmospheric Administration Data Snapshot Details (2019) Accessed 29 Oct 2019
  32. National Oceanic and Atmospheric Administration National Climate Report (2019) Accessed 29 Oct 2019
  33. National Oceanic and Atmospheric Administration Quantitive Precipitation Estimates (2019) Accessed 29 Oct 2019
  34. Neary DG, Swift LWJ (1987) Rainfall thresholds for triggering a debris avalanching event in the southern Appalachian Mountains. In: Costa JE, Wieczorek GF (eds) Reviews in energy. Geology, Volume VII-debris flows avalanches: process, recognition, and mitigation. Geological Society of America, Boulder, pp 81–92CrossRefGoogle Scholar
  35. Ng CWW, Menzies B (2007) Advanced unsaturated soil mechanics and engineering. CRC Press, Taylor and Francis Group, Boca RatonGoogle Scholar
  36. Ng CWW, Wang B, Tung YK (2001) Three-dimensional numerical investigations of groundwater responses in an unsaturated slope subjected to various rainfall patterns. Can Geotech J 38(5):1049–1062CrossRefGoogle Scholar
  37. Nobahar M, Khan MS, Ivoke J, Amini F (2019) Impact of rainfall variation on slope made of expansive Yazoo Clay soil in Mississippi. Transportation Infrastructure Geotechnology, Springer US, Online ISSN 2196-7210, July 27th. CrossRefGoogle Scholar
  38. Olive W, Chleborad A, Frahme C, Shlocker J, Schneider R, Schuster R (1989) Swelling clays map of the conterminous United States. USGS Miscellaneous Investigation Series,
  39. Pomeroy JS (1980) Storm-induced debris avalanching and related phenomena in the Johnstown area, with references to other studies in the Appalachians. Profl. Paper Jl91, U.S. Geological Society, Washington, D.CGoogle Scholar
  40. Rahardjo H, Fredlund DG (1995) Procedures for slope stability analyses involving unsaturated soils. Dev Deep Found Ground Improv Sch, Balkema, pp 33–56Google Scholar
  41. Rahardjo H, Lee TT, Leong EC, Rezaur RB (2005) Response of a residual soil slope to rainfall. Can Geotech J 42(2):340–351CrossRefGoogle Scholar
  42. Rahardjo H, Ong TH, Rezaur RB, Leong EC (2007) Factors controlling instability of homogeneous soil slopes under rainfall. J Geotech Geoenviron Eng 133(12):1532–1543CrossRefGoogle Scholar
  43. Rahardjo H, Leong EC, Rezaur RB (2008) Effect of antecedent rainfall on pore-water pressure distribution characteristics in residual soil slopes under tropical rainfall. Hydrol Process 22(4):506–523CrossRefGoogle Scholar
  44. Rahimi A, Rahardjo H, Leong E (2011) Effect of antecedent rainfall patterns on rainfall-induced slope failure. J Geotech Geoenviron Eng 137(5):483–491CrossRefGoogle Scholar
  45. Ryan C (1988) Bola storm highlights unstable uplands. Nat Bus Rev. Masterton, New Zealand. May 13, 17–19Google Scholar
  46. Skempton AW (1984) Slope stability of cuttings in brown London Clay. In: Proceeding of ninth international conference on soil mechanics and foundation engineering, Tokyo, vol 3, pp 261–270CrossRefGoogle Scholar
  47. Stephens I, Branch A (2013) Testing procedure for estimating fully softened shear strengths of soils using reconstituted material. Engineer Research and Development Center, Vicksburg, MS Geotechnical and Structures Lab, VicksburgGoogle Scholar
  48. Taylor AC (2005) Mineralogy and engineering properties of the Yazoo clay formation. Jackson Group, Master’s Thesis, Mississippi State UniversityGoogle Scholar
  49. Tohari A, Nishigaki M, Komatsu M (2007) Laboratory rainfall-induced slope failure with moisture content measurement. J Geotech Geoenviron Eng 133(5):575–587CrossRefGoogle Scholar
  50. Tsaparas I, Rahardjo H, Toll DG, Leong EC (2002) Controlling parameters for rainfall-induced landslides. Comput Geotech 29(1):1–27CrossRefGoogle Scholar
  51. Wright SG (2005). Evaluation of soil shear strengths for slope and retaining wall stability analyses with emphasis on high plasticity Clays. Federal Highway Administration, Washington, D.C, FHWA/TX-06/5-1874-01-1Google Scholar
  52. Yoshida Y, Kuwano J, Kuwano R (1991) Rain-induced slope failures caused by reduction in soil strength. Soils Found 31(4):187–193CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringJackson State UniversityJacksonUSA

Personalised recommendations