STRUCTURE OR GROUND INVESTIGATING METHOD AND INVESTIGATING DEVICE

摘要

PROBLEM TO BE SOLVED: To easily and highly accurately estimate a position and a dimension of a cavity even in an accuracy-unexpectant place of a geophysical exploration technique without causing adverse influence on strength and administration to a structure or the ground. SOLUTION: While excavating a hole in a cavity investigating object position in lining concrete C by a bit 2 of a rock drill 4 while keeping feed pressure and stroke pressure in a prescribed value, the existence and the size of the cavity V are estimated by a change in a hole excavating speed of the bit 2 and a torque load applied to the bit 2 at that time. COPYRIGHT: (C)2004,JPO