Bridge diagnostics

A team of University of Miami College of Engineering researchers is implementing a self-powered monitor system for bridges.

A team of University of Miami College of Engineering researchers is implementing a self-powered monitor system for bridges, that can continuously check their condition using wireless sensors.

Antonio Nanni, professor and chair of the Department of Civil, Architectural and Environmental Engineering at the university is heading up the project, which is worth almost $14m.

Nanni and his team plan to place the wireless sensors – some as small as a postage stamp – along strategic points inside the 27-year-old Long Key Bridge in the Florida Keys and on a North West 103rd Street 400m steel overpass that leads into Hialeah, Florida.

The sensors, developed by project collaborators Virginia Tech University and New Jersey-based Physical Acoustics Corporation, record all sorts of data, from vibrations and stretching to acoustic waves and echoes emitted by flaws such as cracks.

Even the alkaline levels in the concrete of bridge supports are being measured.

‘The beauty of this project is that the data can be shared with other researchers via a website,’ Nanni says.

‘We could share information with the department of transportation in the UK and show them what’s happening with the Long Key Bridge here in Florida.

‘They would see the data as we see it, in real time.’

Once all the information is culled and analysed, Nanni and his team will form a prognosis of the bridges’ health, and should any defects be found, the decision on how to repair the structures will be made by the Florida Department of Transportation.

Researchers at the University of South Carolina at Columbia are also partners in the study, monitoring a series of bridges in their state and forming diagnoses jointly with the Miami engineers.

Antonio Nanni with graduate students Rosella Ferraro and Felipe Mejia

The project is the second bridge health monitoring study being undertaken by Nanni and his colleagues.

With a group of students, they are also placing sensors along Miami’s Grove Isle Bridge as part of a smaller, one-year study funded by the National Science Foundation.

With the US Federal Highway Administration estimating that more than 70,000 of the nation’s bridges are structurally deficient, the system Nanni and his team develop could be used as a model for monitoring the structural integrity of bridges nationwide and alerting bridge owners to potential dangers.