Engineers Australia

Effect of anisotropy on the bearing capacity and deformation of sand

Alaa H. J. Al-Rkaby, A. Chegenizadeh and H. R. Nikraz


Although the effect of anisotropy on soil behavior due to the parallel alignment of particles remains a subject of great interest, studying its effects on load deformation behavior of stabilized sand has yet to be undertaken. Therefore, this paper presents a study of the behaviour of a laboratory footing model, supported on anisotropic cemented sand, considering two relative densities and three cement contents. The initial anisotropy was induced by preparing samples with different orientations of the bedding plane α (from 0° to 90°). The results show a strong effect of anisotropy, wherein the ultimate pressure of untreated sand took place when α = 0° while the minimum value was achieved at α=60° & 75° for loose and dense sand respectively. Cementation results in clear elimination of variation in bearing capacities, and this significant reduction in anisotropy is accompanied by much improvement in ultimate bearing capacity and stiffness. However, soils with α in the range of 60°–90° still exhibit some little anisotropic behaviour.