Combined bender elements and accelerometers system: Measurement and interpretation

Abstract

Useful to define the stiffness of geomaterials at very small strains, the assessment of seismic wave velocities in the laboratory is currently a worldwide common practice. The combined use of piezoelectric transducers such as bender elements and accelerometers, already proved to be a simple but powerful laboratory tool for seismic wave measurements, helping decrease some subjectivity inherent to BE when used individually. Additionally, the simultaneous use of time and frequency domain signal analysis techniques is considered a useful alternative to reduce error in seismic wave measurements. This paper presents a combined bender elements and accelerometers test setup implemented on a stress-path triaxial chamber as well as a seismic-wave acquisition software that allows simultaneously time and frequency domain analyses on soil samples. Finally, an application study is presented for a monogranular sand tested in triaxial compression at different isotropic stress levels.