Title:
LANDSLIDE SENSOR USING OPTICAL FIBER AND ITS DISPOSING METHOD
Document Type and Number:
Japanese Patent JPH0252222
Kind Code:
A
Abstract:
PURPOSE:To stably and accurately measure landslide for a long time by filling the circumference of a deformation sensor using an optical fiber disposed in a flexible casing tube which is laid under the ground with a filling material having low strength. CONSTITUTION:The casing tube 3 is inserted into an excavated hole 4 which is excavated to the extent of depth which is sufficiently deeper than an expected sliding surface 11 in the ground 10. A material which is easy to be flexed so as to follow the movement of the ground is used for the tube 3. Then, the deformation sensors 1 using the optical fiber are held by spacers 2 which are arranged every prescribed interval and inserted into the tube 3. The spacers 2 can be inserted in the casing tube while they hold the sensors 1 at the prescribed intervals and they are shaped so that the tube 3 is not blocked and the injection of the filling material 5 having low strength is not interfered. Thus, the flexual rigidity of the tube 3 is not raised and the tube 3 is deformed by the movement of the ground caused by the landslide. Besides, the deformation of the tube 3 is propagated to the sensors 1 through the filling material 5.
Inventors:
SEKIDA KINJI
INAMI RYUICHI
MORI KATSUHIRO
IGUCHI KATSUHIKO
INAMI RYUICHI
MORI KATSUHIRO
IGUCHI KATSUHIKO
Application Number:
JP20328488A
Publication Date:
February 21, 1990
Filing Date:
August 17, 1988
Export Citation:
Assignee:
NIPPON STEEL CORP
International Classes:
E21B47/02; G01B11/00; G01B11/16; G01D21/00; (IPC1-7): E21B47/02; G01B11/00; G01B11/16; G01D21/00
Attorney, Agent or Firm:
Yuji Miura