| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of searching a hollow in the ground which can accurately perform measurements, even if there are magnetic components, such as reinforcing iron bars in a buried structure, and to search for a hollow in nondestructive and efficient manner. SOLUTION: The method for searching for a hollow H in the vicinity of a structure buried in the ground installs a plurality of rows of magnetic search machines C at predetermined intervals on the ground to be searched, measures magnetism at the installation, in advance, pours a fluid with a magnetic tracer T mixed in it through one pipe P1 and draws it through the other pipe P2, wherein the pipes P1, P2 are inserted into the depth reaching the hollow and are placed at a predetermined distance in between, allowing the magnetic tracer in which magnetic sand is mixed in muddy water to move in the structure, and measures the moving magnetic tracer by the plurality rows of magnetic search machines C successively. COPYRIGHT: (C)2007,JPO&INPIT |
