According to the Federal Highway Administration (FHWA), our aging infrastructure is a major cause for concern, what with more than half of the 200,000 steel bridges in the U.S. classified as structurally deficient or functionally obsolete. The late June storms in the Northeast corroborated this assessment.
Destruction Moves South
Just as New Englanders were beginning to dry out, the last week of June brought rain and flooding that caused major destruction in the mid-Atlantic region. High water caused the closing of ten bridges connecting New Jersey and Pennsylvania, while in upstate New York a river tore through an I-88 bridge and killed two drivers.
If only that I-88 bridge had had the advantage of sensors. Thankfully, the recent $286 billion Federal Transportation Bill allocated $5 million to help states evaluate nondestructive methods to test growing fatigue cracks in steel bridges.
Advanced Systems for the Future
An article called The Evolution of Advanced Research, in the latest issue of Public Roads, outlines the FHWA's plan to pursue high-risk, high-payoff technologies and innovations to solve critical highway challenges.
And Yunfeng Zhang, an assistant professor of civil and environmental engineering at Lehigh University, recently received a five-year, $400,000 CAREER Award from the National Science Foundation to develop wireless sensor networks for bridges and other structures. Sensors deployed strategically on a bridge, says Zhang, can provide a high-resolution, multi-dimensional picture of the structure's condition, giving engineers vital information about the bridge's performance and, in the aftermath of a catastrophe, its ability to carry traffic.
The future sounds promising, but what about technologies in the here and now?
Capable Technologies Today
There are many. Last month, for instance, we recognized the BRR Fiber Optic Readout System from Blue Road Research—a product that lets you determine damage and strain gradients for any structure in which a fiber-optic sensor can be embedded—with a Best of Sensors Expo award. And Material Technologies (MATECH) Inc.'s Electrochemical Fatigue Sensor (EFS) is also available now.
"The Transportation Equity Act set aside funds for the FHWA to test devices capable of finding growing cracks in bridges as small as 0.010 inches in length and also under the surface." says MATECH CEO Robert M. Bernstein. "Our EFS solution is the only nondestructive testing device able to find growing cracks that small." Further, MATECH says, the technology lets transportation authorities determine which repairs are most urgent.
Selling the States
MATECH has been actively dogging bridge engineers, and says it has received serious interest thus far from several departments of transportation including those in Pennsylvania and Massachusetts.
If you're inspired to take action on this issue, you might follow the lead of Michael J. Pochan, who forwarded the May 16 Today at Sensors entry (which discussed instrumenting roads destined for rebuild) to his state senator. Could your elected officials use some help in understanding the important benefits of current technologies? Anybody from Louisiana or Mississippi reading?