The Neutral Axis and Its Sensitivity to Damage
Speaker: Dorotea H. Sigurdardottir, Graduate Student
Series: MMS Brown Bag Seminars
Location: Engineering Quad E219
Date/Time: Friday, October 18, 2013, 12:30 p.m. - 2:00 p.m.
Structural Health Monitoring (SHM) is the process of continuously or periodically measuring and analyzing structural parameters over long periods of time.
Bridges are essential links which connect regions across major obstacles. The most common bridge systems in the U.S. are composed of beams; in fact, 60% of the U.S. bridge network is composed of beam systems such as multi-, T-, box-, and channel- beams. Therefore, creating monitoring and analysis methods using parameters which are universal for all beam-like structures will have potential wide applicability for existing and new infrastructure. One of these universal parameters is the neutral axis location. The aim of this research is to develop damage detection methods using the neutral axis.
In this talk a focus will be on the results from a test conducted on September 18, 2013. Long-gauge fiber-optic strain and temperature sensors were installed on a scale model of a typical highway overpass in collaboration with Rutgers University. The slab has artificial damage in the concrete. The aim is to evaluate how sensitive the neutral axis is to damage and which sensor configurations provide the most accurate results. Strain measurements from the concrete and steel girders under dynamic truck loading are presented. The results show that the histogram of the neutral axis is sensitive to damage in the concrete slab.