Study on the applicability of the fiber-optic crack detection sensor as a safety technology (Joint research)

Japan Atomic Energy Agency (hereinafter referred to as JAEA) has been conducted a geoscientific research and development project at the Mizunami Underground Research Laboratory and the Horonobe Underground Research Center in order to construct scientific and technological basis for geological disposal. As a collaborative research between JAEA and Tokyo Sokki Kenkyujo Co., Ltd. (hereinafter referred to as TML), we focused on the fiber-optic crack detection sensor developed by TML as a method to detect cracks in the support system that may affect the stability of rock cavern during the operation. To verify long-term safety performance of the sensor for decades, evaluation test of long-term durability of fiber-optic crack detection sensor at the Mizunami Underground Research Laboratory and the Horonobe Underground Research Center were conducted. As a result, we understand that fiber-optic crack detection sensor is applicable measurement method to promptly detect the cracks in the support system. (author)