The Performance Analysis of Distributed Brillouin Corrosion Sensors for Steel Reinforced Concrete Structures

Sensors

Heming Wei¹  Pinglei Zhang¹  Changsen Sun¹  Xuefeng Zhao²  Yanjun Cui²  Xianglong Kong³ 

[1] College of Physics and Optoelectronic Engineering, Dalian University of Technology,Dalian 116024, China;Department of Civil Engineering, Dalian University of Technology, Dalian 116024, China;Power Plant Life Management Research Center, Suzhou Nuclear Power Research Institute,Suzhou 215004, China;

关键词: corrosion monitoring;    reinforced concrete structures;    low-coherent fiber-optic strain sensor;    BOTDA;   

DOI  :  10.3390/s140100431

来源: DOAJ

【 摘 要 】

The Brillouin optical time-domain analysis (BOTDA)-based optical fiber method has been proposed to measure strain variations caused by corrosion expansion. Spatial resolutions of 1 m can be achieved with this kind of Brillouin sensor for detecting the distributed strain. However, when the sensing fiber is wound around the steel rebar in a number of circles in a range of several meters, this spatial resolution still has limitations for corrosion monitoring. Here, we employed a low-coherent fiber-optic strain sensor (LCFS) to survey the performance of Brillouin sensors based on the fact that the deformation measured by the LCFS equals the integral of the strains obtained from Brillouin sensors. An electrochemical accelerated corrosion experiment was carried out and the corrosion expansion was monitored by both BOTDA and the LCFS. Results demonstrated that the BOTDA can only measure the expansion strain of about 1,000 με, which was generated by the 18 mm steel rebar corrosion, but, the LCFS had high sensitivity from the beginning of corrosion to the destruction of the structure, and no obvious difference in expansion speed was observed during the acceleration stage of the corrosion developed in the reinforced concrete (RC) specimens. These results proved that the BOTDA method could only be employed to monitor the corrosion inside the structure in the early stage.

【 授权许可】

Unknown