Could sensors have prevented the disastrous collapse of the Interstate 35W bridge between Minneapolis and St. Paul, Minnesota? Did inspectors miss identifying growing cracks during the federally mandated inspection every two years? No one knows, since the cause of the tragedy has yet to be determined. However, one thing is certain--of the 594,470 U.S. bridges, only four out of the 105,981 steel bridges classified as "structurally deficient" with cracks repaired by road crews, have been diagnosed as effectively cured. The rest are merely re-inspected periodically to see if the repairs were effective--while motorists continue to use them.
"Our company has the only technology that can diagnosis whether repaired bridge cracks have stopped growing," said Bill Berks, director and vice president of government projects at Material Technologies Inc. (Los Angeles). "So far we have inspected repaired cracks on only three bridges in Pennsylvania, and one in Massachusetts, where we found several repaired cracks that were still growing."
Materials Technologies just came out of beta-testing with its crack-diagnosis sensor technology earlier this year, but, already, road-repair crews are resting easier, according to Berks.
"Repair crews love us--in Pennsylvania, for instance, they say 'Now we can sleep well at night, knowing whether our repairs have been effective or not'," said Berks.
As a result, Pennsylvania has contracted to inspect bridge repairs at seven more of its bridges, which are being tested by Materials Technologies sensors right now.