Moving a bridge is no small undertaking, but that's exactly what happened in Oregon last weekend. Back in 2004, cracks were discovered along a 1,100-foot-long truss span of Portland's 87-year-old Sellwood Bridge. For safety, the weight limit was lowered from 32 tons to 10 tons, but this change has diverted thousands of trucks and buses that would otherwise rely on the bridge for daily use. It's time for a new bridge, and to make room for construction while still allowing traffic flow, the old bridge was simply shoved sideways.
On Saturday, the 3400-ton section of bridge was slowly shifted about 66 feet on the west and 33 feet on the east over a 12-hour period. When the truss span was successfully placed onto its temporary supports, it became one of the longest bridge parts ever moved. The old bridge will be converted into a pedestrian walkway crossing the Willamette River and a new bridge will be constructed in the original space to better accomodate Portland's traffic flow.
Take a look at the gallery and the video to view the complexity of this undertaking— engineers used "10 sliding jacks, 40 lifting jacks and a central control system" to ensure everything went as planned. Residents of the Portland area even came out to watch the spectacle unfold.