Health monitoring of civil infrastructures

Health monitoring of civil infrastructure systems is cost-effective and necessary since these systems are generally the most expensive investments/assets in any country. In the U.S. these assets are estimated at $20 trillion. In addition, these systems have long service life compared with any other kinds of commercial product, and are rarely replaceable once they are erected. Yet the feedback and controls on the "state of health" of constructed systems are practically non-existent. Nondestructive evaluation (NDE), sensing and smart structures are essential parts of this feedback and monitoring system for infrastructures. The NSF NDE initiative as well as workshops and related awards/projects are described in this paper.