Shear wave velocity profiles of fill dams

The shear stiffness (Gmax), which is determined from the shear wave velocity (Vs), is an essential parameter in dynamic analyses of fill dams. In this study, Vs profiles were collected and interpreted after comprehensive in situ geophysical seismic surveys of 28 fill dams. The Vs profiles were compared with the empirical formula proposed by Sawada and Takahashi, which was found to overestimate the shear stiffness of a core layer and underestimate that of a shell layer. Regression equations for Vs and Gmax profiles as functions of effective stress were developed for both the core and shell materials. A regression analysis including the mixed effect model was performed to account for the potential bias of data depending on the material types, survey methods, locations, and repeatability. The presented results will improve the prediction of Vs and the reliability of dynamic analyses of fill dams.