Effects of Clay Minerals on Small-Strain Shear Modulus and Damping Ratio of Saturated Clay

This paper explored the impacts of montmorillonite and kaolinite (M-K) ratio as well as consolidation time on small-strain shear modulus and damping ratio of clay soils. A resonant column device was applied to the free vibration column tests. At small shear strain of 0.001%, the shear modulus and damping ratio increased by 57% and 105% respectively when the M-K ratio rose from 0.25 to 4. At higher M-K ratio, the maximum shear modulus grew at a larger rate with consolidation time and then became stable. In contrast, the damping ratio increased more slowly with shear strain at higher M-K ratio. Under a shear strain larger than 0.01%, a negative correlation of the damping ratio with the M-K ratio was found.