Large scale distribution monitoring of FRP-OF based on BOTDR technique for infrastructures

BOTDA(R) sensing technique is considered as one of the most practical solution for large-sized structures as the instrument. However, there is still a big obstacle to apply BOTDA(R) in large-scale area due to the high cost and the reliability problem of sensing head which is associated to the sensor installation and survival. In this paper, we report a novel low-cost and high reliable BOTDA(R) sensing head using FRP(Fiber Reinforced Polymer)-bare optical fiber rebar, named BOTDA(R)-FRP-OF. We investigated the surface bonding and its mechanical strength by SEM and intensity experiments. Considering the strain difference between OF and host matrix which may result in measurement error, the strain transfer from host to OF have been theoretically studied. Furthermore, GFRP-OFs sensing properties of strain and temperature at different gauge length were tested under different spatial and readout resolution using commercial BOTDA. Dual FRP-OFs temperature compensation method has also been proposed and analyzed. And finally, BOTDA(R)-OFs have been applied in Tiyu west road civil structure at Guangzhou and Daqing Highway. This novel FRP-OF rebar shows both high strengthen and good sensing properties, which can be used in long-term SHM for civil infrastructures.

[1]  X. Bao,et al.  Combined distributed temperature and strain sensor based on Brillouin loss in an optical fiber. , 1994, Optics letters.

[2]  M Farhadiroushan,et al.  Temperature and strain dependence of the power level and frequency of spontaneous Brillouin scattering in optical fibers. , 1997, Optics letters.

[3]  Xiaoyi Bao,et al.  Simultaneous strain and temperature measurement in PM fibers using Brillouin frequency, power, and bandwidth , 2004, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[4]  Shunji Kato,et al.  Study on the Monitoring System of Slope Failure Using Optical Fiber Sensors , 2006 .

[5]  T. Horiguchi,et al.  Optical-fiber-attenuation investigation using stimulated Brillouin scattering between a pulse and a continuous wave. , 1989, Optics letters.

[6]  Toshio Kurashima,et al.  Advances in distributed sensing techniques using Brillouin scattering , 1995, Other Conferences.

[7]  Jinping Ou,et al.  Interface strain transfer mechanism and error modification for adhered FBG strain sensor , 2005, Fundamental Problems of Optoelectronics and Microelectronics.

[8]  Liang Chen,et al.  Accurate strain detection and localisation with the distributed Brillouin sensor based on phenomenological signal processing approach , 2006, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[9]  Kazuro Kageyama,et al.  Structural health monitoring of IACC yachts using fiber optic distributed strain sensors: a technical challenge for America's Cup 2000 , 2000, Smart Structures.

[10]  Xiaoyi Bao,et al.  A new fitting method for spectral characterization of Brillouin-based distributed sensors , 2003, Other Conferences.

[11]  Anthony W. Brown,et al.  Advances in distributed sensing using Brillouin scattering , 1998, Smart Structures.

[12]  Lufan Zou,et al.  Investigation of Brillouin effects in carbon coating single-mode fiber using for inspection of pipeline buckling , 2005, SPIE Optics East.

[13]  Aftab A. Mufti.  FRPs and FOSs lead to innovation in Canadian civil engineering structures , 2001 .