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Acta Geotechnica

, Volume 14, Issue 3, pp 749–765 | Cite as

Experimental investigation of microstructural changes in soils eroded by suffusion using X-ray tomography

  • Cong Doan Nguyen
  • Nadia BenahmedEmail author
  • Edward Andò
  • Luc Sibille
  • Pierre Philippe
Research Paper

Abstract

Internal erosion is a complex phenomenon which represents one of the main risks to the safety of earthen hydraulic structures such as embankment dams, dikes or levees. Its occurrence may cause instability and failure of these structures with consequences that can be dramatic. The specific mode of erosion by suffusion is the one characterized by seepage flow-induced erosion, and the subsequent migration of the finest soil particles through the surrounding soil matrix mostly constituted of large grains. Such a phenomenon can lead to a modification of the initial microstructure and, hence, to a change in the physical, hydraulic and mechanical properties of the soil. A direct comparison of the mechanical behaviour of soil before and after erosion is often used to investigate the impact of internal erosion on soil strength (shear strength at peak and critical state) using triaxial tests. However, the obtained results are somehow contradictory, as for instance in Chang’s study (Chang and Zhang in Geotech Test J 34(6):579–589, 2011), where it is concluded that the drained strength of eroded soil decreases compared to non-eroded soil, while both Xiao and Shwiyhat (Geotech Test J 35(6):890–900, 2012) and Ke and Takahashi (Geotech Test J 37(2):347–364, 2014) have come to the opposite conclusion. A plausible explanation of these contradictions might be attributed to the rather heterogeneous nature of the suffusion process and to the way the coarse and fine grains are rearranged afterwards leading to a heterogeneous soil structure, a point that, for now, is not taken into account, nor even mentioned, in the existing analyses. In the present study, X-ray computed tomography (X-ray CT) is used to follow the microstructure evolution of a granular soil during a suffusion test, and, therefore, to capture the induced microstructural changes. The images obtained from X-ray CT reveal indeed that fine particles erosion is obviously not homogeneous, highlighting the existence of preferential flow paths that lead to a heterogeneous sample in terms of fine particles, void ratio and inter-granular void ratio distribution.

Keywords

Heterogeneity Internal erosion Microstructure Suffusion X-ray computed tomography 

Notes

Acknowledgements

A funding provided by Provence-Alpes-Côte d’Azur region is gratefully acknowledged as well as a fruitful partnership with the engineering company SAFEGE. The support of Grenoble Alpes University through the project ERODE (AGIR program) is also acknowledged. We thank P. Charrier and R. Aboul Hosn from Laboratoire 3SR, L.-H. Luu and A. Wautier from Irstea for the help provided during the realization of the tests presented in this paper. We also would like to thank Professors D. Marot and Y. Khidas for their fruitful discussions.

References

  1. 1.
    Benahmed N, Canou J, Dupla J-C (2004) Structure initiale et propriétés de liquéfaction statique d un sable. Comptes rendus mécanique 332(11):887–894zbMATHGoogle Scholar
  2. 2.
    Bendahmane F, Marot D, Alexis A (2008) Experimental parametric study of suffusion and backward erosion. J Geotech Geoenviron Eng 134(1):57–67Google Scholar
  3. 3.
    Bianchi F et al (2018) Tomographic study of internal erosion of particle flows in porous media. Transp Porous Media 122(1):169–184MathSciNetGoogle Scholar
  4. 4.
    Bonelli S (2013) Erosion in geomechanics applied to dams and levees. Wiley, New YorkGoogle Scholar
  5. 5.
    Burenkova V (1993) Assessment of suffusion in non-cohesive and graded soils, in filters in geotechnical and hydraulic engineering. Balkema, Rotterdam, pp 357–360Google Scholar
  6. 6.
    Chang D, Zhang L (2011) A stress-controlled erosion apparatus for studying internal erosion in soils. Geotech Test J 34(6):579–589Google Scholar
  7. 7.
    Desrues J et al (1996) Void ratio evolution inside shear bands in triaxial sand specimens studied by computed tomography. Géotechnique 46(3):529–546Google Scholar
  8. 8.
    Dumberry K, Duhaime F, Ethier YA (2017) Erosion monitoring during core overtopping using a laboratory model with digital image correlation and X-ray microcomputed tomography. Can Geotech J 55(2):234–245Google Scholar
  9. 9.
    Fell R, Fry J-J (2014) Internal erosion of dams and their foundations: selected and reviewed papers from the workshop on internal erosion and piping of dams and their foundations, Aussois, France, 25–27 April 2005. CRC PressGoogle Scholar
  10. 10.
    Fonseca J et al (2014) Microstructural analysis of sands with varying degrees of internal stability. Géotechnique 64(5):405–411Google Scholar
  11. 11.
    Frost J, Park J (2003) A critical assessment of the moist tamping technique. Geotech Test J 26(1):57–70Google Scholar
  12. 12.
    Hall S et al (2010) Discrete and continuum analysis of localised deformation in sand using X-ray [mu] CT and volumetric digital image correlation. Géotechnique 60(5):315Google Scholar
  13. 13.
    Hasan A, Alshibli K (2010) Experimental assessment of 3D particle-to-particle interaction within sheared sand using synchrotron microtomography. Géotechnique 60(5):369Google Scholar
  14. 14.
    Homberg U et al (2012) Automatic extraction and analysis of realistic pore structures from ct data for pore space characterization of graded soil. In: Proceedings of 6th international conference on scour and erosion (ICSE-6). SHF, Paris, France, pp 345–352  Google Scholar
  15. 15.
    Aboul Hosn R et al (2017) Microscale analysis of the effect of suffusion on soil mechanical properties. 11th International Workshop on Bifurcation and Degradation in Geomaterials (IWBDG 2017), May 21-25, 2017, Limassol, Cyprus. In: International workshop on bifurcation and degradation in geomaterials. Springer, Berlin  Google Scholar
  16. 16.
    Aboul Hosn R et al (2018) Effects of Suffusion on the Soil's Mechanical Behavior: Experimental Investigations. 26th Annual Meeting of European Working Group on Internal Erosion EWG-EI, 10-13 September 2018, Milano, Italy. Springer, Internal Erosion in Earthdams, Dikes and Levees - Proceedings of EWG‐IE 26th Annual Meeting 2018, pp 3–15, 2018Google Scholar
  17. 17.
    Indraratna B, Raut AK, Khabbaz H (2007) Constriction-based retention criterion for granular filter design. J Geotech Geoenviron Eng 133(3):266–276Google Scholar
  18. 18.
    Israr J, Indraratna B, Rujikiatkamjorn C (2016) Laboratory investigation of the seepage induced response of granular soils under static and cyclic loading. Geotech Test J 39(5):795–812Google Scholar
  19. 19.
    Ke L, Takahashi A (2014) Triaxial erosion test for evaluation of mechanical consequences of internal erosion. Geotech Test J 37(2):347–364Google Scholar
  20. 20.
    Kenney T, Lau D (1985) Internal stability of granular filters. Can Geotech J 22(2):215–225Google Scholar
  21. 21.
    Kenney T, Lau D (1986) Internal stability of granular filters: reply. Can Geotech J 23(3):420–423Google Scholar
  22. 22.
    Kézdi Á (1979) Soil physics: selected topics (Vol. 25). Elsevier.Google Scholar
  23. 23.
    Li M, Fannin RJ (2008) Comparison of two criteria for internal stability of granular soil. Can Geotech J 45(9):1303–1309Google Scholar
  24. 24.
    Luo Y-L et al (2013) Hydro-mechanical experiments on suffusion under long-term large hydraulic heads. Nat Hazards 65(3):1361–1377Google Scholar
  25. 25.
    Marot D, Bendahmane F, Nguyen HH (2012) Influence of angularity of coarse fraction grains on internal erosion process. La Houille Blanche 6:47–53Google Scholar
  26. 26.
    Mehdizadeh A, Disfani M (2018) Micro scale study of internal erosion using 3D X-ray tomography. The 9th International Conference on Scour and Erosion, Taipei, TaiwanGoogle Scholar
  27. 27.
    Moffat R, Fannin RJ (2011) A hydromechanical relation governing internal stability of cohesionless soil. Can Geotech J 48(3):413–424Google Scholar
  28. 28.
    Moffat R, Fannin RJ, Garner SJ (2011) Spatial and temporal progression of internal erosion in cohesionless soil. Can Geotech J 48(3):399–412Google Scholar
  29. 29.
    Moraci N, Mandaglio MC, Ielo D (2011) A new theoretical method to evaluate the internal stability of granular soils. Can Geotech J 49(1):45–58Google Scholar
  30. 30.
    Sail Y et al (2011) Suffusion tests on cohesionless granular matter: experimental study. Eur J Environ Civ Eng 15(5):799–817Google Scholar
  31. 31.
    Scheuermann A, Kiefer J (2010) Internal erosion of granular materials–identification of erodible fine particles as a basis for numerical calculations. In: 9th International congress of the Hellenic society of theoretical and applied mechanics (HSTAM). Hellenic Society for Theoretical & Applied Mechanics (HSTAM)Google Scholar
  32. 32.
    Skempton A, Brogan J (1994) Experiments on piping in sandy gravels. Geotechnique 44(3):449–460Google Scholar
  33. 33.
    To P, Scheuermann A, Williams D (2018) Quick assessment on susceptibility to suffusion of continuously graded soils by curvature of particle size distribution. Acta Geotech 13(5):1241–1248Google Scholar
  34. 34.
    Tudisco E et al (2017) TomoWarp2: a local digital volume correlation code. SoftwareX 6:267–270Google Scholar
  35. 35.
    Wan CF, Fell R (2008) Assessing the potential of internal instability and suffusion in embankment dams and their foundations. Journal of geotechnical and geoenvironmental engineering, 134(3), 401–407Google Scholar
  36. 36.
    Xiao M, Shwiyhat N (2012) Experimental investigation of the effects of suffusion on physical and geomechanic characteristics of sandy soils. Geotech Test J 35(6):890–900Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Cong Doan Nguyen
    • 1
  • Nadia Benahmed
    • 1
    Email author
  • Edward Andò
    • 2
  • Luc Sibille
    • 2
  • Pierre Philippe
    • 1
  1. 1.Irstea, Aix Marseille Univ, RECOVERAix-en-Provence Cedex 5France
  2. 2.University Grenoble Alpes, CNRS, Grenoble INP, 3SRGrenobleFrance

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