Monday, June 29, 2009
CLEVELAND (AP) — A transportation official warned in a 2007 funding request that a Cleveland bridge was in danger of collapsing, a newspaper reported Sunday.
Bonnie Teeuwen, a deputy director of the Ohio Department of Transportation, wrote that steel plates on the Main Avenue Bridge were overstressed, The Plain Dealer reported.
“The localized buckling indicates that the lower chords are overstressed,” Teeuwen wrote in a September 2007 request to use $150,000 of district funds for emergency repairs. “Failure to repair these chords as soon as possible could result in the collapse of the suspended span.”
In the request, Teeuwen said the chords were thin and buckling and had holes. In some areas, the documents said, the 3‚Ñ8-inch steel had worn to just 1‚Ñ8-inch thick.
The rusted chords — or steel plates joined together — on the 69-year-old bridge were “fracture critical,” meaning if one failed, the entire bridge could crumble in a domino effect known as progressive collapse. The bridge links the Cleveland’s east and west shoreways and carries 35,000 vehicles a day.
The outer lanes of the six-lane bridge were immediately closed to repair the structural steel, and it reopened to all traffic after about a month.
Teeuwen says the alarming wording was necessary to get money quickly to seek repairs.
“If there was any concern about the bridge, we would not have left it open,” she said this month after The Plain Dealer learned of the 2007 repairs.
No specifics about the extent of the problem were revealed because the media did not ask, Teeuwen said.
The bridge was similar in design to the Interstate 35 bridge in Minneapolis that had fallen a month earlier, killing 13 people.
“There was a hole you could see through; it was all wobbly,” said Mike Malloy, the district’s bridge engineer.
The Main Avenue Bridge appears to be in better shape than its truss-span counterpart, the Inner Belt Bridge. That bridge is so deteriorated that trucks are banned, lanes are closed, and it is slated for replacement in 2013.
But under its bright-blue paint, the steel that holds up the Main Avenue Bridge is thinner and weaker than ODOT officials thought. The span was downgraded from satisfactory to poor in its most recent inspection done last summer, indicating considerable deterioration, but officials did not restrict its use.
The 2007 problem was discovered only after layers of rust were removed from beams and other steel when the bridge was sandblasted for painting, Teeuwen said.
The current extent of the steel beam corrosion will be measured this year with an ultrasonic thickness gauge to determine what repairs are needed now, she said.
Ultimately, the bridge should be replaced because it is an aging under-deck truss span similar to the Minnesota bridge, Teeuwen said. But she said replacing it isn’t a priority, and finding the money to pay for it will be a challenge.
The Main Avenue Bridge, rising 120 feet above the Flats, is Ohio’s longest elevated structure at 8,000 feet, according to the Encyclopedia of Cleveland History.
The bridge closed for 18 months in 1991 and 1992 for a $62 million renovation that included a new deck, upgraded drainage and replacement of some deteriorated beams and steel deck-support brackets.