Ground cavity detection manner and its device

摘要

PURPOSE: To provide a method and device for detecting ground cavity for inexpensively, quickly, and widely detecting a cavity under the ground from the surface of the ground without any destruction. ;CONSTITUTION: A sensor 5 for measuring vibration is installed on a ground surface 4 to measure a constant slight movement. The horizontal component spectrum and vertical component spectrum of the measured constant slight move are obtained and the spectrum ratio of the obtained horizontal component spectrum to the vertical component spectrum is obtained, thus obtaining a vibration characteristic curve and detecting a cavity 3 existing under the ground according to the shape of the obtained vibration characteristic curve.;COPYRIGHT: (C)1997,JPO