A precise evaluation of shear wave velocity, V s, is a crucial issue in the design of
foundations subjected to dynamic loading, liquefaction evaluation and soil improvement
control. Laboratory techniques such as resonant column (RC) and bender element (BE)
have been developed over the years to measure V s. At low strain (γ< 10-3), techniques
based on piezoelectric elements (eg BE) can be considered superior to RC since they can
be used in conventional geotechnical devices (eg triaxial, oedometer, DSS, etc.). However ...