Abstract: An energy-injecting virtual-mass (EIVM) resonant column system was employed to investigate the small strain behavior of dry sand; and the effects of effective mean normal stress, density of soil samples, amplitude of shear strain, as well as number of loading cycles on shear modulus and damping ratio are studied. The test results show that the shear modulus increases with effective mean normal stress and soil density, while the damping ratio exhibits the opposite response. Moreover, the effects of effective mean normal stress on the small strain behavior of dry sand are more than those of soil density. As the shear strain increases, the shear modulus become smaller; but the damping ratio become larger. The number of loading cycles has no significant effects on shear modulus, but it influences the damping ratio to a quite extent.

Key words: dry sand；small strain behavior；shear modulus, damping ratio；number of loading cycles