More 60-Second Tech
Four years ago this week, the Minneapolis I-35W bridge collapse killed 13 people and injured 145. More recently, more than one in four U.S. bridges were found to be either structurally deficient or functionally obsolete, according to a 2009 study by the U.S. Society of Civil Engineers.
Visual inspection is still the go-to method of judging a bridge’s integrity. But researchers have been working on sensor arrays that could reveal problems long before a roadway is on the brink.
For example, University of Maryland electrical engineering researcher Mehdi Kalantari is designing a wireless early warning system made up of tiny sensors that can monitor a bridge's structural integrity and transmit that data to a central computer for analysis.
Kalantari's sensors are less than five millimeters thick and sense and measure structural parameters, communicate data and harvest energy from ambient light and ambient radio waves. The sensors are designed to be affordable: an average-sized highway bridge would need about 500 sensors costing a total of about $10,000. Such systems could help avoid catastrophes that cost far more than prevention.
—Larry Greenemeier
[The above text is a transcript of this podcast.]



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4 Comments
Add CommentI'm sorry but there is a huge difference between structurally deficient and functionally obsolete. So when you combine the to stats and say "More recently, more than one in four U.S. bridges were found to be either structurally deficient or functionally obsolete, according to a 2009 study by the U.S. Society of Civil Engineers" it makes this thing sound sensationalist. I agree that we have a problem with infrastructure in the US, but you won't make a convincing point by spinning stats.
Reply | Report Abuse | Link to thisTo my earlier point, I could say the 50% of people either have AIDS or are male. Alright, I'll let it die now.
Reply | Report Abuse | Link to thisI am constantly amazed at the sloppiness of the writing on this scientific site
Reply | Report Abuse | Link to thisGoing further than "justanobody", I will say that lack of a provided definition for "structurally deficient" is problematic since "deficient" may not always be "unsound/unsafe" but include inadequate. In fact this is just what the linked site states: "These [structurally deficient] bridges are not unsafe, but must post limits for speed and weight."
Reply | Report Abuse | Link to thisThe lack of definitions in SciAm articles such as this contributes to the confusion of many readers and probably even of the writers themselves.