Crack detection of structures using optical time domain reflectometry (OTDR) method

Crack detection technique for concrete structures is developed in this paper. This method utilized Optical Time Domain Reflectormetry (OTDR) method that broadly used in the field of optical science. Currently several crack detection techniques, such as visual inspection, crack gage, ultrasonic detection test, are used. But these methods are not economical and are time-consuming issue. Therefore, easy and economical method of detecting cracks on the surface of concrete structure or welded part of steel structure have been developed in this research, this technique utilizes optical fiber and OTDR equipment. Concrete beam model tests are performed to verify the usefulness of this technique. Results of these tests show that developed technique can detect the location of the cracks easily and correctly. Further task is to testify the method of detecting cracks on welded part of steel structure with a performance of model test and apply it to a real structure.