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Stability Evaluation of Un-braced Cuts


In this study, the critical depth of un-braced open cuts is investigated using physical and numerical modeling carried out by the centrifuge machine at the Iran University of Science and Technology and a FISH code developed in the finite difference software, FLAC, respectively. The undrained shear strength of the soil was measured using Unconfined Compression Test (UCT), Miniature Vane Shear Test (MVST), and Pocket Penetrometer Test (PPT) and the results were used to develop a statistical correlation between the soil water content and its strength. In addition, upper and lower bound limit analysis solutions were used as benchmarks to verify the results. Finally, the values of critical excavation depth obtained through numerical analysis and centrifuge modeling in this study were compared with those estimated by the limit analysis and limit equilibrium methods.

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  1. 1.

    Abramson LW (2002) Slope stability and stabilization methods. John Wiley & Sons, New York

    Google Scholar 

  2. 2.

    Zhu D, Lee C, Jiang H (2003) Generalised framework of limit equilibrium methods for slope stability analysis. Géotechnique 53(4):377–395

    Article  Google Scholar 

  3. 3.

    Ugai K, Leshchinsky D (1995) Three-dimensional limit equilibrium and finite element analyses: a comparison of results. Soils Found 35(4):1–7

    Article  Google Scholar 

  4. 4.

    Yu H, Salgado R, Sloan S, Kim J (1998) Limit analysis versus limit equilibrium for slope stability. J Geotech Geoenviron Eng 124(1):1–11

    Article  Google Scholar 

  5. 5.

    Cheng Y, Lansivaara T, Wei W (2007) Two-dimensional slope stability analysis by limit equilibrium and strength reduction methods. Comput Geotech 34(3):137–150

    Article  Google Scholar 

  6. 6.

    Alejano L, Ferrero AM, Ramírez OP, Fernández M (2011) Comparison of limit-equilibrium, numerical and physical models of wall slope stability. Int J Rock Mech Min Sci 48(1):16–26

    Article  Google Scholar 

  7. 7.

    Chen WF (1975) Limit analysis and soil plasticity, developments in geotechnical engineering. Elsevier, Amsterdam

    Google Scholar 

  8. 8.

    Giger MW, Krizek RJ (1975) Stability analysis of vertical cut with variable corner angle. Soils Found 15(2):63–71

    Article  Google Scholar 

  9. 9.

    Giger MW, Krizek RJ (1976) Stability of vertical corner cut with concentrated surcharge load. J Geotech Eng Div 102(1):31–40

    Google Scholar 

  10. 10.

    Michalowski R (1995) Slope stability analysis: a kinematical approach. Géotechnique 45(2):283–293

    MathSciNet  Article  Google Scholar 

  11. 11.

    Donald I, Chen Z (1997) Slope stability analysis by the upper bound approach: fundamentals and methods. Can Geotech J 34(6):853–862

    Article  Google Scholar 

  12. 12.

    Kim J, Salgado R, Lee J (2002) Stability analysis of complex soil slopes using limit analysis. J Geotech Geoenviron Eng 128(7):546–557

    Article  Google Scholar 

  13. 13.

    Farzaneh O, Askari F (2003) Three-dimensional analysis of nonhomogeneous slopes. J Geotech Geoenviron Eng 129(2):137–145

    Article  Google Scholar 

  14. 14.

    Stanier SA, Tarantino A (2013) An approach for predicting the stability of vertical cuts in cohesionless soils above the water table. Eng Geol 158:98–108

    Article  Google Scholar 

  15. 15.

    Naylor D (1982) Finite elements and slope stability. Numerical methods in geomechanics. Springer, Netherlands

    Google Scholar 

  16. 16.

    Cascini L (1983) A numerical solution for the stability of a vertical cut in a purely cohesive medium. Int J Numer Anal Meth Geomech 7(1):129–134

    Article  Google Scholar 

  17. 17.

    Matsui T, San K (1992) Finite element slope stability analysis by shear strength reduction technique. Soils Found 32(1):59–70

    Article  Google Scholar 

  18. 18.

    Lane P, Griffiths D (1997) Finite element slope stability analysis–why are engineers still drawing circles. In: Proceeding of 6th international symposium on numerical models in geomechanics pp 589–593

  19. 19.

    Cala M, Flisiak J, Tajduś A (2004) A Slope stability analysis with modified shear strength reduction technique. In: the 9th international symposium on landslides: evaluation and stabilization pp 1085–1089

    Chapter  Google Scholar 

  20. 20.

    Drucker DC, Prager W (1952) Soil mechanics and plastic analysis or limit design. Quart Appl Math 10:157–165

    MathSciNet  Article  Google Scholar 

  21. 21.

    Heyman J (1973) The stability of a vertical cut. Int J Mech Sci 15:845–854

    Article  Google Scholar 

  22. 22.

    Josselin de Jong G (1978) Improvement of the lower bound for the vertical cut off in a cohesive frictionless soil. Géotechnique 28:197–201

    Article  Google Scholar 

  23. 23.

    Taylor DW (1948) Fundamentals of soil mechanics. Wiley, New York

    Google Scholar 

  24. 24.

    de Buhan P, Dormieux L, Maghous S (1993) Stabilité d’un talus vertical: amélioration de la borne cinématique. Comptes Rendus de l’Académie des Sciences 317(II):13–136

    MATH  Google Scholar 

  25. 25.

    Bekaert A (1995) Improvement of the kinematic bound for the stability of a vertical cut-off. Mech Res Commun 22:533–540

    Article  Google Scholar 

  26. 26.

    Pastor J, Thai TH, Francescato P (2000) New bounds for the height limit of a vertical slope. Int J Numer Anal Meth Geomech 24:165–182

    Article  Google Scholar 

  27. 27.

    Dysli M, Fontana A (1983) Deformation around the excavations in clayey soil. Ecole Polytechnique Fédérale de Lausanne, Laboratoires de Mécanique des Sols et des Roches pp 634–642

  28. 28.

    Banerjee P, Kumbhojkar A, Yousif N (1988) Finite element analysis of the stability of a vertical cut using an anisotropic soil model. Can Geotech J 25(1):119–127

    Article  Google Scholar 

  29. 29.

    Phoon KK, Kulhawy FH (1999) Characterization of geotechnical variability. Can Geotech J 36(4):612–624

    Article  Google Scholar 

  30. 30.

    Babu GS, Mukesh M (2004) Effect of soil variability on reliability of soil slopes. Géotechnique 54(5):335–337

    Article  Google Scholar 

  31. 31.

    Cho SE (2007) Effect of spatial variability of soil properties on slope stability. Eng Geol 92(3):97–109

    Article  Google Scholar 

  32. 32.

    Griffiths D, Huang J, Fenton GA (2009) Influence of spatial variability on slope reliability using 2-D random fields. J Geotech Geoenviron Eng 135(10):1367–1378

    Article  Google Scholar 

  33. 33.

    Kasama K, Zen K (2011) Effects of spatial variability of soil property on slope stability. In: Vulnerability, uncertainty, and risk analysis modelling and management. ASCE, Reston 691–698

    Google Scholar 

  34. 34.

    Jamshidi Chenari R, Zamanzadeh M (2016) Uncertainty assessment of critical excavation depth of vertical unsupported cuts in undrained clay using random field theorem. Sci Iran 23(3):864–876

    Google Scholar 

  35. 35.

    Taylor R (2003) Geotechnical centrifuge technology. Blackie Academic and Professional, London

    Google Scholar 

  36. 36.

    Roessig LN, Sitar N (2006) Centrifuge model studies of the seismic response of reinforced soil slopes. J Geotech Geoenviron Eng 132(3):388–400

    Article  Google Scholar 

  37. 37.

    González L, Abdoun T, Dobry R (2009) Effect of soil permeability on centrifuge modeling of pile response to lateral spreading. J Geotech Geoenviron Eng 135(1):62–73

    Article  Google Scholar 

  38. 38.

    Ling HI, Wu MH, Leshchinsky D, Leshchinsky B (2009) Centrifuge modeling of slope instability. J Geotech Geoenviron Eng 135(6):758–767

    Article  Google Scholar 

  39. 39.

    Sommers A, Viswanadham B (2009) Centrifuge model tests on the behavior of strip footing on geotextile-reinforced slopes. Geotext Geomembr 27(6):497–505

    Article  Google Scholar 

  40. 40.

    Ling H, Ling HI (2012) Centrifuge model simulations of rainfall-induced slope instability. J Geotech Geoenviron Eng 138(9):1151–1157

    Article  Google Scholar 

  41. 41.

    Rajabian A, Viswanadham B, Ghiassian H, Salehzadeh H (2012) Centrifuge model studies on anchored geosynthetic slopes for coastal shore protection. Geotext Geomembr 34:144–157

    Article  Google Scholar 

  42. 42.

    Stewart MA, McCartney JS (2013) Centrifuge modeling of soil-structure interaction in energy foundations. J Geotech Geoenviron Eng 140(4):1–11

    Google Scholar 

  43. 43.

    ASTM D422–63 (2007) Standard test method for particle-size analysis of soils. ASTM International, West Conshohocken

    Google Scholar 

  44. 44.

    ASTM D854–14 (2014) Standard test methods for specific gravity of soil solids by water pycnometer. ASTM International, West Conshohocken

    Google Scholar 

  45. 45.

    ASTM D4318 (2010) Standard test methods for liquid limit, plastic limit, and plasticity index of soils. ASTM International, West Conshohocken

    Google Scholar 

  46. 46.

    ASTM D2166 (2016) Standard test method for unconfined compressive strength of cohesive soil. ASTM International, West Conshohocken

    Google Scholar 

  47. 47.

    Koumoto T, Houlsby G (2001) Theory and practice of the fall cone test. Géotechnique 51(8):701–712

    Article  Google Scholar 

  48. 48.

    Trauner L, Dolinar B, Mišič M (2005) Relationship between the undrained shear strength, water content, and mineralogical properties of fine-grained soils. Int J Geomech 5(4):350–355

    Article  Google Scholar 

  49. 49.

    Jamshidi Chenari R, Karimian A (2011) Realization of undrained shear strength of natural deposits using random field theory. J Comput Methods Eng 30(2):21–43 (Persian)

    Google Scholar 

  50. 50.

    Chen T, Cheng Z, Wang G, Liu E, Dai F (2017) Centrifuge model test on unsaturated expansive soil slopes with cyclic wetting–drying and inundation at the slope toe. Int J Civ Eng.

    Article  Google Scholar 

  51. 51.

    Mehrzad B, Haddad A, Jafarian Y (2016) Centrifuge and numerical models to investigate liquefaction induced response of shallow foundations with different contact pressures. Int J Civ Eng 14(2):117–131

    Article  Google Scholar 

  52. 52.

    Schofield AN (1980) Cambridge geotechnical centrifuge operations. Géotechnique 30(3):227–268

    Article  Google Scholar 

  53. 53.

    Taylor R (1995) Centrifuges in modeling: principles and scale effects, Geotechnical centrifuge technology. Blackie Academic and Professional, London

    Google Scholar 

  54. 54.

    Garnier J, Gaudin C, Springman SM, Culligan PJ, Goodings D, Konig D, Kutter B, Phillip R, Randolph MF, Thorel L (2007) Catalogue of scaling laws and similitude questions in geotechnical centrifuge. Int J Phys Model Geo 7(3):1–23

    Google Scholar 

  55. 55.

    Shahnazari H, Salehzadeh H, Askarinejad A (2008) Determination of virtual cohesion in unsaturated sand trenches, using geotechnical centrifuge. Int J Civ Eng 6(1):1–9

    Google Scholar 

  56. 56.

    Taylor DW (1937) Stability of earth slopes. Boston Society of Civil Engineers, Boston

    Google Scholar 

  57. 57.

    Atkinson JH (1981) Foundations and Slopes: an introduction to applications of critical state soil mechanics. John Wiley and Sons, New York

    Google Scholar 

  58. 58.

    Terzaghi K (1943) Theoretical soil mechanics. John Wiley and Sons, New York

    Book  Google Scholar 

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Correspondence to Habib Shahnazari.

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Shahnazari, H., Chenari, R.J., Fard, M.K. et al. Stability Evaluation of Un-braced Cuts. Int J Civ Eng 16, 1361–1369 (2018).

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  • Critical depth
  • Centrifuge test
  • Limit analysis
  • Upper- and lower-bound solutions