Quarterly Webinar Series
Hosted by INSPIRE UTC
Lab-on-Sensor for Structural Behavior Monitoring: Theory and Applications
DATE/TIME: September 28, 2017, 11:00 AM–12:00 PM Central Time (US and Canada)
PRESENTED BY: Genda Chen, Ph.D., P.E., F.ASCE, Missouri University of Science and Technology
There are over 600,000 bridges in the U.S. National Bridge Inventory (NBI). Nearly 50% of them rapidly approach their design life and deteriorate at an alarming rate, particularly under an increasing volume of overweight trucks. Visual inspection as the current practice in bridge management is labor intensive and subjective, resulting in inconsistent and less reliable element ratings. Lab-on-sensor technologies can provide supplemental mission-critical data to the visual inspection for both qualitative and quantitative evaluations of structural conditions, and thus critical decision-making of cost-effective strategies in bridge preservation.
In this presentation, the design and operation characteristics of highway bridges are first reviewed to establish the needs for structural behavior monitoring in order to align monitoring outcomes with daily practices in bridge preservation. The responses of steel-and concrete-grider bridges to earthquake/tsunami events and the deterioration of aging bridges are then introduced to demonstrate the types of structural limits to prevent through planned, monitored, and evaluated maintenances. Next, a lab-on-sensor design theory is presented and applied to detect and assess structural behaviors such as concrete cracking, foundation scour, and steel corrosion. For each mechanical or electrochemical behavior, the theory includes three steps: (1) Extension of the behavior from a structural element to its nearby deployed sensor with a special mechanism, (2) Calibration of the sensed parameter with the behavior of the sensor mechanism and (3) Behavior correlation of the sensor mechanism with the nearby structural element. For crack detection and assessment, coax cable sensors are designed, fabricated, calibrated and applied to an in-service low-volume bridge based on the propagation and change of electromagnetic waves in a coax cable. For foundation scour detection and assessment, smart rocks with embedded magnet(s) are designed, fabricated, calibrated and applied to an in-service high-volume bridge based on the change of magnetic fields around a smart rock deployed around a foundation. For steel corrosion detection and assessment, Fe-C coated long period fiber grating sensors are designed, fabricated, calibrated and applied to reinforced concrete specimens in laboratory based on the change in wavelength of the light transmitting through the gratings. Finally, the accuracy, resolution and measurement range of various sensors are discussed before this presentation is concluded.
Professor Genda Chen, Ph.D., P.E., F. ASCE, F. SEI
Professor and Robert W. Abbett Distinguished Chair in Civil Engineering
Director, System and Process Assessment Research Laboratory (SPAR Lab)
Director, INSPIRE University Transportation Center (INSPIRE UTC)
Associate Director, Mid-America Transportation Center (MATC)
Missouri University of Science and Technology (Missouri S&T)
Email: firstname.lastname@example.org, email@example.com
URL: http://web.mst.edu/~gchen/, http://inspire-utc.mst.edu
Dr. Chen received his Ph.D. degree from State University of New York at Buffalo in 1992 and joined Missouri S&T in 1996 after over three years of bridge design, inspection, and construction practices with Steinman Consulting Engineers (later merged to Parsons Transportation Group) in New York City. He was granted two patents and authored over 350 publications in structural health monitoring, structural control, interface mechanics and deterioration, bridge engineering, and multi-hazard effects. He received the 1998 National Science Foundation CAREER Award, the 2004 Academy of Civil Engineers Faculty Achievement Award, and the 2009, 2011, and 2013 Missouri S&T Faculty Research Awards. He is Chair of the 9th International Conference on Structural Health Monitoring of Intelligent Infrastructure in 2019, Associate Editor of the Journal of Civil Structural Health Monitoring, Editorial Member of Advances in Structural Engineering, a council member of the International Society for Structural Health Monitoring of Intelligent Infrastructure, and an executive member of the U.S. Panel on Structural Control and Monitoring. He was a member of post-disaster reconnaissance teams after the 2005 Category III Atlantic Hurricane, the 2008 M7.9 China Earthquake, the 2010 M8.8 Chile Earthquake, and the 2011 M9.0 Great East Japan Earthquake. He was elected to ASCE Fellow in 2007 and Structural Engineering Institute (SEI) Fellow in 2013. In 2016, he was nominated and inducted into the Academy of Civil Engineers at Missouri S&T.