Based on acoustic-electric conversions theory, a new experiment method for Rayleigh surface wave field observation is put forward.In the method, the acoustic source is an ultrasonic transducer, and however, the acoustic receivers are replaced by electrodes to measure the acoustic-electric signals, which are caused by the transform from acoustic energy actived by the source to electric energy within the vicinity of each electrode. Two rectangular blocks which are, respectively, made of Granite and sandstone, are used as models to test the method. In the tests, the electrodes located on the surface of the models are arranged in a line and the source transducer is located in the line with some offsets. The observed data are shown as multi-channel recording, and then the apparent velocities of the first arrives are estimated by their slopes. The expeiments show that the apparent velocities of the first arrives are remarkably smaller than the velocities of P-wave, and are nearly equal to the velocities of surface waves estimated from P-wave velocity and theory possion ratio in corresponding models. By analysis, the acustic-electric signals observed in the experiment are the Rayleigh surface wave, and the physical experiment method for Rayleigh surface wave field based on acoustic-electric conversions is feasible.
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