An Approach for Description of Elastic Parameters of Cross-Anisotropic Saturated Soils

Abstract

The processes of deposition and consolidation in natural soils or compaction in fill materials will typically produce soils that are initially cross-anisotropic (also known as transversely isotropic or orthotropic) in terms of both small strain elastic behaviour and large strain plastic behaviour. For small strain elastic behaviour, five elastic parameters are required to fully describe cross-anisotropic soils such as two Young’s moduli (E_v in vertical direction and E_h in horizontal direction), two Poisson’s ratios (v_vh horizontal strain due to vertical strain and v_hh horizontal strain due to horizontal strain) and an independent shear modulus such as G_hv(a shear wave horizontally transmitted with vertically polarised). These five elastic parameters have been expressed in different fashions in the literature. In this paper results from derivations showed that it is possible to express the elastic parameters for cross-anisotropic soils in a different way than that expressed in the literature using as a function of independent measurements of two shear moduli and two constrained moduli from three pairs of bender/extender elements BEEs fitted on a cross-anisotropic soil sample in a triaxial apparatus and measuring or assuming the value of v_hh using combination of triaxial testing system and bender/extender element testing system.