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Abstract: The mechanical behavior of sand is very complex, and depends on factors including confining pressure, density, and drainage condition. A soil mass can be contractive or dilative when subjected to shear loading, and eventually reaches an ultimate state, referred to as the critical state in soil mechanics. Conventional approach to explore the mechanical behavior of sand mainly relies on the experimental tests in laboratory. This paper gives an alternative view to this subject using discrete element method (DEM), which has attracted much attention in recent years. The implementation of the DEM is carried out by a series of numerical tests on granular assemblies with varying initial densities and confining pressures, under different test configurations. The results demonstrate that such numerical simulations can produce correct responses of the sand behavior in general, including the critical state response, as compared to experimental observations. In addition, the DEM can further provide details of the microstructure evolutions during shearing processes, and the resulting induced anisotropy can be fully captured and quantified in the particle scale.

[1] Arthur, J.R.F., Menzies, B., 1972. Inherent anisotropy in a sand. Geotéchnique, 22:115-128.

[2] Bishop, A.W., Henkel, D.J., 1962. The Measurement of Soil Properties in the Triaxial Test. Edward Arnold Ltd., London.

[3] Cundall, P.A., Strack, O.D.L., 1979. A discrete numerical model for granular assemblies. Geotéchnique, 29:47-65.

[4] Drescher, A., 1976. An experimental investigation of flow rule for granular assemblies. Géotechnique, 26:49-65.

[5] Ishihara, K., 1996. Soil Behavior in Earthquake Geotechnics. Oxford Science Publications. Clarendon Press, Texas, p.350.

[6] Ishihara, K., Tatsuoka, F., Yasua, S., 1975. Undrained deformation and liquefaction of sand under cyclic stresses. Soils and Foundations, 15(1):29-44.

[7] Itasca Consulting Group Inc., 2005. PFC^2D User’s Manual. Itasca Consulting Group, Inc., Minneapolis, USA.

[8] Johnson, K.L., 1985. Contact Mechanics. The Press Syndicate of the University of Cambridge, Cambridge, p.464.

[9] Li, X., 2006. Micro-scale Investigation on the Quasi-static Behavior of Granular Material. Ph.D Thesis, the Hong Kong University of Science and Technology, p.355.

[10] Li, X.S., Dafalias, Y.F., 2000. Dilatancy for cohesionless soils. Geotéchnique, 50:449-460.

[11] Lobo-Guerrero, S., Vallejo, L.E., 2005. Discrete element method evaluation of granular crushing under direct shear test conditions. Journal of Geotechnical and Geoenvironmental Engineering, 131(10):1295-1300.

[12] Lu, M., McDowell, G.R., 2006. The importance of modelling ballast particle shape in the discrete element method. Granular Matter, 9(1-2):69-80.

[13] Oda, M., 1999. Fabric Tensor and Its Geometrical Meaning. In: Oda, M., Iwashita, K. (Eds.), Mechanics of Granular Materials: an Introduction. A.A. Balkema, Rotterdam, p.27-34.

[14] Oda, M., Konishi, J., Nemat-Nasser, S., 1980. Some experimentally based fundamental results on the mechanical behaviour of granular materials. Géotechnique, 30:479-495.

[15] Oda, M., Konishi, J., Nemat-Nasser, S., 1982. Experimental micromechanical evolution of strength of granular materials: effects of particle rolling. Mechanics of Materials, 1(4):269-283.

[16] Schofield, A.N., Wroth, P., 1968. Critical State Soil Mechanics. McGraw-Hill Book Company, London, p.464.

[17] Verdugo, R., Ishihara, K., 1996. The steady state of sandy soil. Soils and Foundations, 36(2):81-92.

[18] Wang, J., Dove, J.E., Gutierrez, M.S., 2007. Discrete-continuum analysis of shear banding in the direct shear test. Géotechnique, 57(6):513-526.

[19] Wood, D.M., 1990. Soil Behavior and Critical State Soil Mechanics. Cambridge University Press, Cambridge, p.486.

[20] Yang, Z.X., 2007. Investigation of Granular Soil Behavior―a Micromechanical Approach. Report to the University of Hong Kong, Hong Kong.