The determination of shear wave velocity (Vs) using bender elements can be affected by the
near-field effect. This phenomenon hinders the identification of the S-wave arrival time of an
output signal. Multiple alternatives have been presented to counteract these effects, including
the use of wavelet transforms during the last decade. In this article, the Haar wavelet is used
because of the simplicity and speed of calculation. The determination of S-wave arrival time in
signals influenced by the near-field effect is performed by setting an explicit event with a high
value of energy at a specific time, in relation to the scale average energy in different levels of
multiresolution analysis. The results show that regardless of the input frequency, the S-wave
arrival time values are very similar, and the near-field effect is not observed when wavelet
approach is used to determine the S-wave arrival times, unlike when applying other traditional
interpretation approaches.

A. Fernández Lavín and E. Ovando Shelley, “Haar Wavelet Transform for Arrival Time
Identification in Bender Element Tests,” Geotechnical Testing Journal 43, no. 4 (July/August
2020): 937–949.