Development and Application of a Portable Vibroseis Source for Acquisition and Analysis of Seismic Surface Wave Data

The paper is devoted to development of a portable vibrating unit and study of its applicability in generating seismic waves. The solution to developing a portable vibrating unit problem capable of generating a stable seismic signal in the target frequency range is very important. Existing solutions are cumbersome and cannot be widely applied in engineering seismic exploration. The paper describes in detail the design of the vibrator source, the stages of output laptop signals testing, the power amplifier, and haptic transducer control. Signals with different frequency sweeps were used during field acquisition. The recorded data were processed by multichannel analysis of surface waves. As a result of comparing the amplitude spectra and dispersion images of the surface wave, it was found that a hyperbolic (low-dwell) sweep signal generates a surface wave train in the entire frequency range (10-150 Hz), but does not produce high-frequency interference waves in cement concrete pavement as opposed to other sweep signals and sledgehammers. Based on the field data processing results, we reconstructed a one-dimensional shear-wave velocity model for soils and concluded on the success, practicability, and increased (compared to a sledgehammer) efficiency of using the developed vibrator source for acquisition and analysis of surface wave data for engineering seismology problems. The undoubted advantages of using a vibration source are controllability of the frequency content and its repeatability. The use of such vibroseis devices combined with stationary seismic recording systems is a promising direction for solving seismic monitoring problems.