LAUSR

The seismic response of soil depends on proper evaluation and use of soil dynamic properties, including shear modulus and damping ratio at various strain levels. Despite extensive studies on the shear modulus and damping ratio of saturated soils, research on the dynamic properties of unsaturated fine-grained soils — especially at high suction — is limited. This study aims to investigate the dynamic properties of loess at a variety of initial states resulting from different specimen preparation techniques (reconstituted, recompacted, and intact) and their evolutions due to suction-induced desiccation. Results of resonant column tests show that at initial states, the specimen preparation technique has a negligible effect on the normalized modulus (G/Gmax) and damping degradation pattern, while the influence becomes significant at a high suction (40 MPa). This is attributed to the microstructural evolution of specimens with different initial states that were subjected to suction-induced desiccation. More spe...