Interfacial changes of optical fibers in the cementitious environment

摘要: Embedded optical fiber sensors have recently been employed for strain and crack monitoring in concrete structures. The performance of the sensor is strongly affected by fiber/matrix interface. For monitoring, effective stress transfer between matrix required. A high interfacial bond therefore desirable. On other hand, sensing may rely on debonding bending, which only possible with a weak bond. In cementitious environment, properties are known to vary time, this affect long-term embedded sensors. objective present investigation study changes when specimens containing fibers (with different coatings) subject environmental conditions including wet curing, wetting/drying freezing/thawing. Fibers removed from examined under SEM. Also, pull-out prepared tested. results show that test can reveal significant behaviour cannot be detected SEM examination. demonstrated useful technique characterization time dependent behavior