Dependency of a Small-Strain Shear Modulus on Suction Stress

The small-strain shear modulus G₀ is a fundamental property in geotechnical problems such as wave propagation, liquefaction, and soil-structure interaction. The stress dependency of G₀ was examined by determining the particle contact force using the suction stress theory for soils under unsaturated conditions. The correlation between G₀ and suction stress characteristic curve (SSCC) was found for soils under a zero-total-stress boundary conditions. Dependencies of G₀ and suction stress on soil moisture are demonstrated to follow the same pattern but differ by a constant scalar. A linear relationship between G₀ and suction stress with a strong correlation to the soil water retention was found. As such, the suction stress theory was verified to be able to represent the particle contact force for unsaturated soils under zero total stress boundary conditions.