Articles & Applications for Optical Sensing

Remote Health Monitoring of a High Performance Steel Bridge Using Fiber Optic Technology by J.D. Doornink, B.M. Phares, A. Abu-Hawash, T.J. Wipf, D.J. Hemphill, L.F. Greimann "In early 2004, the Iowa Department of transportation (DOT) completed construction of Iowa's first High Performance Steel (HPS) bridge ...the Bridge Engineering Center at Iowa State University has developed a continuous Structural Health-Monitoring (SHM) system to monitor and record the performance of the HPS bridge for a two-year period. With this system, the bridge performance can be evaluated at any point in time...(read entire article) Copyright 2004; posted with permission of the Bridge Engineering Center of the Iowa State University Research Park. For more information regarding the Bridge Engineering Center, go to their website. Smart FRP-OFBG Bars and their Application in Re-inforced Concrete Beams by Z. Zhou, J.P. Ou & B. Wang "Fiber Reinforced Polymer (FRP) has become more and more popular as construction material in civil engineering due to its advantages of corrosion-resistance, high strength, nonmagnetic, fatigue-resistance... Optical Fiber Bragg Grating (OFBG) is now widely accepted as [a] smart sensor due to its advantages of electric-magnetic resistance, small size, distributing measurement, durability, and so on. Combined the strength properties of FRP with the sensing properties of OFBG, a new kind of smart FRP-OFBG composite bars has been developed.... The experiment of FRP-OFBG re-inforced concrete beams under static load has been done, and ....(read entire article) Copyright 2004; posted with permission of the Harbin Institute of Technology in China.

To be presented

Growing Market Acceptance for Fiber-Optic Solutions in Civil Structure
By T.W. Graver

Owners must ensure safety of their civil structures even as use for many extends well beyond their design lifetime. Traditionally, most structures rely on strict maintenance procedures, visual inspections, and very few sensors. But maintenance is very expensive, visual inspections can miss critical problems, and conventional sensors can fail in harsh environments. Can fiber-optic sensing (FOS) address these issues? This is not a new question, but there are some new answers. This paper highlights three structures where FOS is used, and describes the associated successes and challenges for each application. Many successes are coupled to improved FOS tools: better sensor packages, simpler and less expensive instrumentation, improved installation techniques, and more efficient data analysis tools. Examples of each are provided. Particular attention is given to the economics of instrumenting civil structures - when and how it pays. Conclusions include recommendations for future developments that will further accelerate FOS acceptance and use.

Note: this paper will be delivered on October 27, 2004 at Optics East in Philadelphia, PA, USA.

Fiber Bragg Grating Sensing for Structural Health Monitoring of Civil Structures
By J. D. Doornink, T.W. Graver, J.P. Ou, B. M. Phares and Z. Zhou

Structural Health Monitoring (SHM) is fast becoming a highlight of both research and applications in civil engineering. One key driver is the ever-improving function and cost of fiber-optic sensing (FOS) systems. To date, FOS has been used on hundreds of civil structures around the world. This paper focuses on two initiatives that rely on FOS. Researchers from Iowa State University's Bridge Engineering Center demonstrate a novel approach to SHM data management, analysis and presentation. Preliminary results are shown and links to live data are provided. At the Harbin Institute of Technology, civil engineers are studying local damage on large-span bridges. Current work focuses on solving key practical challenges for several existing and new large spans.

Note: this paper will be delivered at the International Symposium on Advances and Trends in Fiber Optics and Applications October 11-14, 2004. The symposium is organized by Chongqing University in Chongqing, China.