EXPERIMENTAL STUDY ON SHEAR MODULUS AND DAMPING RATIO CHARACTERISTICS OF SILTY SOIL IN THE DELTA OF YELLOW RIVER

Based on resonance column method and dynamic triaxial tests, shear modulus and damping ratio characteristics of saturated silty soil (silt, silty sand or silty clay) in the delta of Yellow River were studied in detail. The results show that the silt content has a great influence on dynamic shear modulus. Normalized shear modulus and damping ratios vs. shear strain curves are both affected by confining pressure, and the effect of clay content is not significant. By comparing test results with the modulus reduction and damping ratio curves for sand and saturated clay suggested by Seed, once can conclude that the dynamic characteristics of deformation of the silty soil is very similar to those of sand, but there is a distinct difference. The trend of the modulus reduction and damping ratio curves from our test is also different with silty soils in other area. Modified Hardin-Drnevich models and logistic models are used to describe the trend of the normalized modulus reduction curves and damping ratios vs. shear strain curves in the paper.