This paper presents micromechanics models to estimate resilient properties of unbound aggregate materials. Micromechanics models account for the effect of particle orientation and the ratio of the normal contact stiffness to shear contact stiffness among particles. The results demonstrate that aggregate orientation and shape influence the level of inherent anisotropy, which has a substantial effect on the pavement responses that impact pavement design. The micromechanics analysis predicted an inherent anisotropy (ratio of horizontal to vertical modulus) ranging from 1.0 to 0.4. The effect of this increased anisotropy on the performance of a pavement with an unbound aggregate base is substantial.
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Kim, SH., Kim, N. Micromechanics analysis of granular soils to estimate inherent anisotropy. KSCE J Civ Eng 11, 145–149 (2007). https://doi.org/10.1007/BF02823894
- unbound aggregate