Dependencies of Shear Wave Velocity and Shear Modulus of Soil on Saturation

Abstract

AbstractShear wave propagation in soil is a physical phenomenon and has been used widely for monitoring and seismic property assessment in geotechnical engineering. Shear wave velocity Vs and small-strain shear modulus G0 are the key parameters in defining material response to various dynamic loadings. To date, the dependencies of Vs and G0 on saturation, especially in high suction range, are still not well understood because of the limited testing methodology and experimental evidence. In this study, the authors present a new laboratory instrumentation of measuring shear wave propagation in different types of unsaturated soils. Low relative humidity and water mist injection environment are used for measuring shear wave velocity under both drying and wetting conditions. Bender element technique was used to measure the shear wave responses. Step function was used as excitation, and determination of a first arrival time was identified and consistently used for all shear wave measurements. Shear wave evoluti...