Triaxial tests on the fluidic behavior of post-liquefaction sand

Liquefaction-induced ground deformation is a major cause of structural damage during earthquakes. However, a better understanding of seismic liquefaction is needed to improve earthquake hazard analyses and mitigate structural damage. In this paper, a dynamic triaxial test apparatus was employed to investigate the fluidic characteristics of post-liquefaction sand. The specimens were vibrated to the point of liquefaction by dynamic loading, and then the liquefied sand was further sheared by triaxial compression in an undrained manner. It was found that a non-Newtonian fluid model can accurately describe the shear stress and the shear strain rate of post-liquefaction sand during undrained triaxial compression. The apparent viscosity, a major parameter in a constitutive model of a non-Newtonian fluid, decreases with an increase in the shear strain rate.