Application of piezoelectric in seismic geotechnical engineering and measurement of compressive wave velocity using piezoelectric

Piezoceramic material has been used in engineering measurement and control. When used in geotechnical testing, the material can work as a wave transmitter or a wave receiver. Among the piezoelectric sensors , the bender element and the bending disk are used for testing. While the bender element is used to generate and receive shear waves, the bending disk is used to produce and detect P-waves. Though, several researchers have successfully employed these tests for characterizing the soil mass based on the shear wave velocities, determination of the ‘‘time lag’’ between the input and output waves remains debatable. Even, the existing literature does not clearly present the problem with respect to the frequency of excitation, detection of first arrival, the wave shape and near field effects. With this in view, this investigation was made to capture the performance of piezoceramic elements. Details of the methodology are presented in this paper and special attention has been paid to address various problems (i.e., wave attenuation, frequency of excitation, detection of first arrival, the wave shape and near field effects) that are associated with signal interpretation. The cross correlation is a procedure which resolves uncertainties in travel time. Near field effects, wave attenuation and frequency of excitation can be effectively taken into consideration by matching the measured signal with the analytical solution. It is recommended to use sinusoidal wave shapes since compression wave velocity obtained by means of square wave was usually greater than ones result of sinusoidal waves.

Recommended citation: Jafarzadeh, Fardin; Fadaei, Mansour; ,Application of piezoelectric in seismic geotechnical engineering and measurement of compressive wave velocity using piezoelectric,6th International Conference on Seismology and Earthquake Engineering,2011
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