MEASUREMENT OF BURIAL DEPTH OF SUBAQUEOUS POWER CABLE

摘要

PURPOSE:To make it possible to monitor the underground depth over the full length by a method wherein light is cast on an optical fiber and then a temperature distribution in the longitudinal direction of a power cable is detected due to Raman scattering light of the light cast on the optical fiber. CONSTITUTION:An optical combined subaqueous power cable 1 wherein optical fibers 2 are combined is buried in the water bottom soil 4 at the depth of L. The optical fibers 2 in the buried optical combined subaqueous power cable 1 are used as a licensor. Light from a laser light source or an LED light source is cast on the optical fibers 2 and then the intensity of Raman scattering light contained in back scattering light of the light cast on the optical fibers 2 is detected. By this, data about a temperature distribution in the longitudinal direction of the optical compound subaqueous power cable 1 can be attained. By this method, a change in the underground depth L of the cable 1 can be known accurately and the underground depth L can be monitored over the full length of the cable 1.