Multichannel analysis of surface waves method for shallow soil profile exploration.

Abstract

In order to explore shallow soil properties in a noninvasive manner, a multichannel analysis of surface waves method was employed to obtain soil shear wave velocity profile up to a couple of meters. In the study, an electromechanical shaker operating in a frequency‐sweeping mode was placed on the ground to excite Rayleigh waves propagating along the surface. A laser Doppler vibrometer (LDV) was used as a noncontact receiver to detect the surface vibration. The LDV was mounted on an aluminum frame and driven by a stepper motor to move along a straight line. Multichannel surface vibrations were obtained and analyzed to determine the dispersive curve; i.e., the Rayleigh wave velocity as a function of frequency. An inversion algorithm was used to transform the dispersion curve into the shear wave velocity profile. This technique can be developed for the applications of levee and dam evaluation as well as shallow soil properties imaging and characterization.