engleski

Principles of Fiber optic Sensors and Applications to Structural Monitoring

Maintenance of reinforced concrete structures and planning of the work on their remediation requires effective monitoring techniques. Most used deformation monitoring techniques use extensometers based on dial gauges or LVDT'’ s and tensometers. Main disadvantage of these techniques is their sensitivity to temperature variations, mechanical and chemical influences. During last ten years fibre optical sensors (FOS) showed all their advantages for structural deformation monitoring. They have high accuracy and long term stability, there is no need for calibration, it can be used for wide range of temperatures, in strong electromagnetic fields and chemical aggressive environments. Thanks to their small thickness, it can be embedded into structures, which makes possible deformation measurements for different depths or in different layers. FOS has capability to measure statically or dynamically, at frequencies sufficient for use as accelerometers. Only one optical fibre can be used to measure temperature and deformation at many locations and sensors can be kilometres long. Disadvantage of optical fibre measuring systems is expensive detection devices. Paper describes physical principles on which deformation FOS can be based, their suitability for different measuring requirements, and their various applications. Fibre optical sensors except deformation can measure other parameters, such as pressure, temperature, acceleration, magnetic fields and chemical parameters.

Deformation monitoring; Fibre optic sensors; Reinforced concrete structures

nije evidentirano