Parameter Identification of Liquefiable Soil in Free Field Tested on Shaking Table

Abstract:

The characteristics of liquefiable soil during earthquake excitation of free field were identified based on multiple acceleration records in shaking table tests.The time histories of cyclic shear stress and shear strain in the soils were evaluated from the accelerations recorded in the soil.These histories were used to estimate variation of soil dynamic shear moduli and material damping characteristics with shear strain amplitude.Soil stiffness properties agree well with those obtained based on laboratory tests.The material damping computed from acceleration records was however much higher than that independently measured in laboratory tests.Pore pressure buildup was found to affect shear wave velocity in the soil and weaken soil stiffness.