Principal Investigator: Genda Chen
Sponsors & Partners
Center for Infrastructure Engineering Studies
About this Project
Brief Project Description & Background
This project is aimed to characterize the ruggedness and signal loss of carbon-coated optical fibers and validate their performance as sensors. Currently, telecom-grade optical fibers are widely used in civil engineering for strain and temperature measurements. These fibers are very fragile and easy to break during installation and measurement. One solution is to integrate optical fibers into fiber-reinforced polymer (FRP) materials to form so-called â€œsmart FRP tapeâ€ (Bastianini et al., 2003). Another solution is to strengthen the coating on optic fibers. The latter will be the focus of this study.
This project is to characterize carbon-coated fiber ruggedness against shear action and lateral compression, to study the optical signal loss along carbon optical fibers, and to apply fibers to strain and temperature measurements in concrete
The expected results and products from this study will be a set of characterization data to show the ruggedness of carbon optical fibers, the maximum distance as sensors, and their ability of monitoring the complete structural behavior of concrete members up to collapse. It is also anticipated that the issues related to interfacial behavior between fibers and concrete such as bonding will be identified for further investigation. The findings will enable the measurements of information that is critical to the safety of transportation structures.
Brillouin-scattering Optical Time Domain Reflectometry (BOTDR) is a viable technology for simultaneous, distributed strain and temperature measurements for miles-long transportation structures. It is a promising tool to ensure the smooth operation and safety of bridge structures that are key links in surface transportation networks or between various transportation modes, i.e., from airport to train station. Currently, telecom-grade optical fibers are widely used in civil engineering for strain and temperature measurements. These fibers are very fragile and easy to break during installation and measurement. In order to understand the ultimate behavior of structures, more rugged optical fibers such as carbon/polyimide coated fibers were recently proposed. One laboratory study on two single fibers indicated that new carbon/polyimide coated fibers can sustain a maximum strain of up to 4%, which can survive any local crack in concrete members or buckling in steel members once they are installed on the structural members. This project is aimed to characterize the ruggedness and signal loss of carbon-coated optical fibers and validate their performance as sensors.