The Sellwood Bridge has a truss 23m high and 8.5m wide and crosses the Willamette River in the US state of Oregon. It links south west Portland to its south east business district and suburbs.
In the 19 January operation, Omega Morgan will move the bridge in one piece. The old bridge will then become a temporary route for the 30,500 vehicles that cross it each day, while work begins on the new US$307.5 million bridge, due to be completed in 2016.
“We are really pleased to be involved in this important, complex and exciting project said John McCalla, CEO and president of Omega Morgan.
Both Omega Morgan and general contractor Slayden/Sundt Joint Venture have used this detour bridge method for other projects. “Omega Morgan has moved bridges weighing upwards of eight million pounds, but this one does offer some additional challenges,” said McCalla.
The company’s chief engineer, Ralph DiCaprio, said the company welcomes the challenges. “This is why we like what we do. There’s something different on every project,” he said.
Devising a strategy to move the bridge in one piece helped Omega Morgan win the contract after showing that it would save time, money and duplication of efforts.
The plan is to use hydraulic jacks to lift the bridge onto skid gear and then to move and mount it on new piers that have been built in the river. The old bridge will then become the detour while construction begins on the new bridge.
The decision was made to replace the Sellwood Bridge because it cannot handle the current volume of traffic, has a low rating on a federal bridge rating, and buses and heavy trucks are restricted fromusing the bridge.
