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Indexed by:Journal Papers

Date of Publication:2019-11-01

Journal:STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL

Included Journals:SCIE

Volume:18

Issue:5-6

Page Number:1862-1873

ISSN No.:1475-9217

Key Words:Corrosion monitoring; corrosion-induced deformation; low-coherent fiber-optic sensor; structure-health monitoring; pre-stressed concrete cylinder pipes

Abstract:The corrosion-induced expansion of pre-stressed concrete cylinder pipes shapes a major determining factor in the durability of most pipeline systems. However, a structure extended in a very large span and accompanied by a slow corrosion-induced structural damage is still a challenge in practice. Here, a low-coherent fiber-optic interferometry is proposed for in situ measuring the corrosion-induced expansion by directly circling the sensing optical fiber on the outer surface of the pipe. Since the accuracy of the absolute deformation measurement by the low-coherent fiber-optic interferometry can reach 3-5 mu m, we are able to improve the sensitivity by choosing the length of the sensing fiber. In the experiment, we employ 50-m sensing fiber; therefore, a resolution of about 0.1 microstrains had been approached. We chose 12 places along the pipeline as the corrosion-induced expansion monitoring points. On monitoring for about half a year, a non-uniform interface in structure, such as the repaired places, was found as a key factor of the corrosion-induced expansion development, which could be a reference for the further health care of the pipeline structures.