Small-strain dynamic properties of siliceous-carbonate sand under stress anisotropy

Abstract

Small-strain dynamic properties of sands are commonly estimated through the correlations basically developed by the experimental results of isotropically consolidated specimens. In reality, however, the in-situ stress state of soils is not necessarily isotropic. Several resonant column tests were conducted on reconstituted samples of a coastal siliceous-carbonate sand in a variety of initial relative density and consolidation stress. The results indicate that despite the noticeable effect of initial stress anisotropy on the values of maximum shear modulus Gmax, the values of minimum damping ratio Dmin are almost independent of initial stress ratio. In a preceding paper, the authors proposed a correction factor for two siliceous and calcareous sands which correlates the shear modulus in anisotropic stress condition to the isotropic shear modulus. It is demonstrated herein that the proposed formula is precise for the siliceous-carbonate sand of the present study. The proposed empirical relationship is then compared with a correction factor proposed by others for shear modulus of sands in stress anisotropy condition.