For more than a year, the Ohio Department of Transportation has monitored the Anthony Wayne Bridge’s suspension cables with acoustic sensors to identify any areas where they might be weak.
Today, department personnel start another diagnostic procedure: Cutting open the outer sheath in a few selected spots to check for corrosion on the cables inside.
The bridge’s exploratory surgery will require lane closings for three weeks, beginning today on the eastbound side and Friday evening on the westbound side.
It’s part of prep work for the bridge’s major overhaul, scheduled to start next spring, although state officials said last week a planned 19-month shutdown to traffic may not occur until 2014.
“When that detour will start, we don’t know, because it will depend on the contractor’s schedule,” Mike Gramza, the department’s district construction engineer in Bowling Green.
Planners now assume 2014 because of delivery time for steel and materials once a contract is awarded in March, he said, but the winning bidder “could decide to go right away” with replacing two of the Anthony Wayne’s approach spans and other work that officials say can be done only with the bridge closed to traffic.
The 1931-vintage structure, also known as the High Level Bridge, is the last suspension bridge on the Ohio state highway system, carrying State Rts. 2, 51, and 65 over the Maumee River. It last underwent major repairs 15 years ago, when its concrete deck was resurfaced, some suspender cables were replaced, its main suspension cables were wrapped with weatherproofing material, and other work was done.
Mr. Gramza said Friday the acoustic monitoring so far has not indicated any broken cables, but beginning today, contractors will cut into the sheathing in four locations and drive wedges in between the bundled cables.
“They will get a good look inside to see if there’s any corrosion, and the extent of that corrosion,” he said.
The eastbound right lane will be closed starting at 7 a.m. today and is scheduled to reopen by 5 p.m. Nov. 19. The westbound right lane is to close at 7 a.m. Friday and reopen by 5 p.m. Nov. 30. Traffic delays are likely, especially during the afternoon rush hour while the eastbound lane closing is in place and during the morning rush hour for the westbound work.
The bridge’s overhaul will be highlighted by the removal and replacement of the first approach span at either end of its main suspension spans. Those two approach spans are built on deck trusses that are “fracture critical,” meaning that if key components should fail, there is no structural backup to prevent collapse.
Their design also means that for practical purposes, they can’t be taken down and replaced one half at a time, Mr. Gramza said.
Even if that could be done, the ODOT engineer said, deck replacement on the main spans would create a weight imbalance that would be difficult and expensive to correct. If it is even possible, doing the project under traffic would add at least a year to its schedule and $10 million to its cost, already estimated between $35 million and $40 million.
The project will include replacing expansion joints, any necessary cable repairs or replacements, and — under a separate, follow-up contract — repainting the bridge.
While the Anthony Wayne Bridge is closed, traffic will be detoured to the DiSalle Bridge on I-75. The Martin Luther King, Jr., Bridge is likely to attract much of its traffic as well.
The bridge work is expected to require two five-day closings of Miami Street at the Anthony Wayne bridge, and other neighborhood streets that go under the bridge are likely to be closed for varying periods too.
Contact David Patch at:email@example.com or 419-724-6094.