Shear wave velocity of sand during liquefaction by bender elements

摘要

The velocity of shear wave propagation was measured by using a pair of piezoceramic bender elements, fixed at the top cap and pedestal of the triaxial apparatus. The element at the top cap operated as a wave transmitter, while the one located at the pedestal operated as a wave receiver. In order to confirm the validity of this bender element method, following element tests were performed: 1) cyclic triaxial tests at small strain level, 2) cyclic tortional shear tests at small strain level and 3) measuring shear wave velocity of triaxial specimen. Comparisons between shear stiffness measured by bender elements, shear stiffness by cyclic triaxial test and tortional shear tests at small strain were considered. Moreover, changes of shear stiffness during isotropic compression, liquefaction and post-liquefaction were also considered.