EXPERIMENTAL STUDY ON INTERMEDIATE RADIOACTIVE WASTE REPOSITORY MONITORING BASED ON DISTRIBUTED OPTICAL FIBER SENSOR

Abstract

 Sensor-based monitoring is expected to be a method for long-term evaluation of radioactive waste disposal facility. Especially, distributed optical fiber sensor (DFOS) is one of the best candidates, because it has various advantages, such as small and lightweight, no power for sensor, and multi-channel sensors which lead to less impact on radioactive barrier. The authors experimentally investigate to evaluate applicability of DFOS in the facility, while parameters to be monitored after closure of the facility have been selected. Specifically, long-term durability and pressure measurement feasibility is evaluated by laboratory tests. In mock-up test, temperature and strain distribution measurement are applied, and crack on the lower diffusion layer is successfully detected by local strain changes.