Advertisement

Acta Geotechnica

, Volume 13, Issue 6, pp 1467–1472 | Cite as

Why the OCR may reduce the small strain shear stiffness of granular materials?

  • Xiaoqiang Gu
  • Shuocheng Yang
Short Communication
  • 281 Downloads

Abstract

The small strain shear stiffness G0 of the soil is of interest and importance in both theory and practice. It is expected that for granular materials G0 would slightly increases with over-consolidation ratio (OCR). However, laboratory tests indicate that G0 may decrease with increasing OCR, especially for loose specimens, which is counterintuitive. To explore the underlying mechanism, discrete element method (DEM) is used to investigate the effect of OCR on G0. The DEM simulations successfully capture the laboratory observations. The analyses at the particulate level reveal that the decrease in small strain stiffness is mainly due to the decreases in coordination number and the uniformity of contact force distribution during unloading process.

Keywords

Discrete element method Micromechanics OCR Poisson’s ratio Small strain stiffness 

Notes

Acknowledgements

The work presented in this paper is supported by National Key Research and Development Program (Grant No. 2016YFC0800200), National Natural Science Foundation of China (Grant Nos. 51308408, 41772283) and Fundamental Research Funds for the Central Universities. These supports are gratefully acknowledged.

References

  1. 1.
    Alarcon-Guzman A, Chameau JL, Leonards GA, Frost JD (1989) Shear modulus and cyclic undrained behavior of sands. Soils Found 29(4):105–119CrossRefGoogle Scholar
  2. 2.
    Cascante G, Santamarina JC (1996) Interparticle contact behavior and wave propagation. J Geotech Eng Div ASCE 122(10):831–839CrossRefGoogle Scholar
  3. 3.
    Ezaoui A, Di Benedetto H (2009) Experimental measurements of the global anisotropic elastic behavior of dry Hostun sand during triaxial tests, and the effect of sample preparation. Géotechnique 59(7):621–635CrossRefGoogle Scholar
  4. 4.
    Gu X (2012) Dynamic properties of granular materials at the macro and micro scales. Dissertation, The University of Hong KongGoogle Scholar
  5. 5.
    Gu X, Yang J (2013) A discrete element analysis of elastic properties of granular materials. Granul Matter 15(2):139–147CrossRefGoogle Scholar
  6. 6.
    Gu X, Yang J, Huang M (2013) Laboratory measurements of small strain properties of dry sands by bender element. Soils Found 53(5):735–745CrossRefGoogle Scholar
  7. 7.
    Gu X, Huang M, Qian J (2014) DEM investigation on the evolution of microstructure in granular soils under shearing. Granul Matter 16(1):91–106CrossRefGoogle Scholar
  8. 8.
    Gu X, Yang J, Huang M, Gao G (2015) Bender element tests in dry and saturated sand: signal interpretation and result comparison. Soils Found 55(5):952–963CrossRefGoogle Scholar
  9. 9.
    Gu X, Hu J, Huang M (2017) Anisotropy of elasticity and fabric of granular soils. Granul Matter 19(2):33CrossRefGoogle Scholar
  10. 10.
    Hardin BO (1978) The nature of stress–strain behavior for soils. In: Proceeding of specialty conference on earthquake engineering and soil dynamics. ASCE, Pasadena, pp 3–90Google Scholar
  11. 11.
    Hardin BO, Richart FE (1963) Elastic wave velocities in granular soils. J Soil Mech Found Div ASCE 89(SM1):39–56Google Scholar
  12. 12.
    Hoque E, Tatsuoka F (1998) Anisotropy in elastic deformation of granular materials. Soils Found 38(1):163–179CrossRefGoogle Scholar
  13. 13.
    Hoque E, Tatsuoka F (2004) Effects of stress ratio on small-strain stiffness during triaxial shearing. Géotechnique 54(7):429–439CrossRefGoogle Scholar
  14. 14.
    Itasca (2009) Particle flow code (PFC3D) manual. Itasca Consulting Group Inc, MinneapolisGoogle Scholar
  15. 15.
    Kiyota T, De Silva LIN, Sato T, Koseki J (2006) Small strain deformation characteristics of granular materials in torsional shear and triaxial tests with local deformation measurements. In: Hoe I et al (eds) Soil stress–strain behavior: measurement, modeling and analysis: a collection of papers of the geotechnical symposium in Rome Ling. Springer, Dordrecht, pp 557–566Google Scholar
  16. 16.
    Kokusho T (1980) Cyclic triaxial test of dynamic soil properties for wide strain range. Soils Found 20(2):45–60CrossRefGoogle Scholar
  17. 17.
    Kumar J, Madhusudhan BN (2010) Effect of relative density and confining pressure on Poisson ratio from bender–extender element tests. Géotechnique 60(7):561–567CrossRefGoogle Scholar
  18. 18.
    Kuwano R, Jardine RJ (2002) On the applicability of cross-anisotropic elasticity to granular materials at very small strains. Géotechnique 52(10):727–749CrossRefGoogle Scholar
  19. 19.
    Muir Wood D, Maeda K (2008) Changing grading of soil: effect on critical states. Acta Geotech 3:3–14CrossRefGoogle Scholar
  20. 20.
    Otsubo M, O’Sullivan C, Sim WW, Ibraim E (2015) Quantitative assessment of the influence of surface roughness on soil stiffness. Géotechnique 65(8):694–700CrossRefGoogle Scholar
  21. 21.
    Tatsuoka F, Shibuya S, Teachavorasinskun S (1991) Discussion on “Shear modulus and cyclic undrained behavior of sands”. Soils Found 31(2):202–209Google Scholar
  22. 22.
    Thornton C (2000) Numerical simulations of deviatoric shear deformation of granular media. Géotechnique 50(1):43–53CrossRefGoogle Scholar
  23. 23.
    Wang R, Fu P, Zhang J, Dafalias Y (2016) DEM study of fabric features governing undrained post-liquefaction shear deformation of sand. Acta Geotech 11(6):1321–1337CrossRefGoogle Scholar
  24. 24.
    Wang R, Fu P, Zhang J, Dafalias Y (2017) Evolution of various fabric tensors for granular media toward the critical state. J Eng Mech 143(10):04017117CrossRefGoogle Scholar
  25. 25.
    Yang J, Gu X (2013) Shear stiffness of granular material at small strain: Does it depend on grain size? Geotechnique 63(2):165–179CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Geotechnical Engineering and Key Laboratory of Geotechnical and Underground Engineering of the Ministry of EducationTongji UniversityShanghaiChina

Personalised recommendations