ABSTRACT
A trial investigation was undertaken to evaluate the feasibility of applying a uniquely designed optic fiber sensor for detection of water leakage in a metro tunnel in Tokyo. To conduct effective maintenance works for underground infrastructures constructed several decades ago, it is essential to perform a thorough inspection for damage states of concrete structures that may be induced by water leakage from cracks over time. The results of the investigation indicated that the proposed sensor is capable of detecting water leakage both in laboratory and field, suggesting that the method would be readily applicable for practical use in maintenance works for aged concrete structures.
