Geophysics-based approach to predict triaxial undrained and drained compressive behavior in soft soils

Geophysical measurements such as shear wave velocity are typically used to characterize subsurface conditions. Since the shear wave velocity can be measured both in the field and in the laboratory, there is continuous interest in using shear wave velocity to define the stress state of the soil. This study aimed to develop a geophysics-based approach to predicting the triaxial behavior of cohesive soils. Laboratory tests with bender elements were performed for silt-predominant samples from the state of Kentucky. A function to relate mean effective stresses and shear wave velocities was adapted from the measured behavior to predict undrained and drained triaxial behavior. Using the previous function in conjunction with a hypoplastic model for soft soils expressed in stress invariants, the deviatoric strains, volumetric strains, and excess porewater pressures developed during shearing were predicted. The proposed methodology performed very well in simulating the various soils under undrained and drained conditions.