From IEEE Spectrum online:
Sensors are starting to prove themselves in the biggest, most complex bridges, but the technology isn’t ready for the hundreds of thousands of smaller ones
The 2.9-kilometer Rion-Antirion Bridge in Greece, with its 300 sensors, is a testament to how smart a piece of infrastructure can be. It routinely tells operators when an earthquake, frequent in those parts, or high winds warrant shutting down traffic.
“The bridge tolls are meant to collect thousands of euros per day,” says Alexandre Chaperon, an engineer at the company that designed the system, Advitam, in Vienna, Va. “Without the monitoring system, the bridge would be closed after every earthquake, more than three days in some cases, instead of 5 minutes.”
Dozens of the largest and most complex bridges in the world are already studded with strain and displacement gauges, three-dimensional accelerometers, tiltmeters, temperature sensors, and other instruments. They are wired to central data-acquisition units—though some newer bridges have wireless systems—which collect and analyze the information and relay it to engineers, in hopes of catching signs of distress before human inspectors could. With the United States injecting US $27.5 billion into revamping the country’s roadways and bridges as part of an $800 billion economic stimulus effort, it might seem like a perfect opportunity to add smarts to more bridges.
Rad the complete article here.