Temporary Multi-Span Panel Bridge
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Temporary Multi-Span Panel Bridge Emergency Replacement for I-5 Bridge Collapse in Skagit County WA After the collapse of the I-5 Bridge over the Skagit River in A crane-assisted launch was also not possible since the existing Burlington, WA, the WSDOT had to find a quick and safe solution multi-span through truss would be an obstruction during the to solving a financial disaster in the making. In conjunction with placement of the temporary bridge. The only practical way to place Atkinson Construction and the WSDOT, an Acrow 700 XS panel the bridge was to perform a full cantilever launch. bridge was commandeered as an emergency temporary bridge over the Skagit River. The over height vehicle responsible for the accident impacted Special consideration and design input was needed for the Acrow bridge pedestals. They were designed with the capability of sliding the bridges sideways on Hilman rollers, which was necessary because the upper segments of the 1960’s through truss, compromising the through truss was 8 feet narrower than the Acrow structure. its structural capabilities. This caused the bridge to collapse Once the pedestals were in place, bridge one (north bound lanes) was into the river with no loss of life. Consequently, it created a traffic launched, jacked down onto Hilman rollers and moved eastwards, nightmare with an immediate financial impact; Costco reported a cantilevered over the bridge pedestals, and positioned out of the loss of $1 million in one day as a result of the traffic gridlock. way to make room for the south bound bridge. The second bridge It was imperative that the highway bridge structure be repaired as speedily as possible. The WSDOT awarded Atkinson Construction the was then jacked down and positioned on permanent bridge bearings, 6 inches from bridge one. emergency contract 2 days after the incident, and Acrow became part The deck was then situated, asphalted, and the temporary bridge was of the team to engineer a rapid solution for the bridge replacement. formally opened on June 16, 2013 ready to receive the average daily Two 24 foot wide by 160 foot span Acrow bridges were designed to replace the old 53 foot wide, 160 foot long bridge. However, to commandeer this layout required a large crane which can take multiple weeks and no suitable crane was available at the time. traffic volume of around 70,000 cars and trucks. The Acrow bridge will be in place for approximately 4 months until a permanent bridge can be constructed and moved into place.

“I’d like to add my congratulations to all of you and to your team members. Please pass on our appreciation for their hard work to make this happen. Replacing a collapsed bridge with a temporary structure in less than a month is a fantastic achievement. You made it look easy, even though it was extremely difficult. Well done and thank you all for making this happen.” WSDOT Official Washington State Department of Transportation Specifications Bridge length: Deck surface: Bridge design: Acrow supplied two 160 linear feet (48.8M) Asphalt overlay (A) Panel chords, diagonals 7 verticals, panel...