All together the series of pontoons that form the floating bridge required approximately 3600 ft of post-tensioning.

Pontoon bridge washington state. The six-lane bridge carries State Route 520 across Lake Washington from Seattle to its eastern suburbs. The bridge on State Route SR 104 connects the Kitsap Peninsula with the Olympic Peninsula. WSDOT and contractor Kiewit-General built a 4-acre casting-basin facility to stage construction of 33 pontoons for the new SR 520 floating bridge.

Wed January 26 2011 - West Edition. The old Lake Washington Floating Bridge that carried US 10 at the time of this photo and later I-90. While pre-1900 bridges are rare the state has an impressive collection of 20th century bridges including unique cantilever truss designs Pierce Countys concrete truss McMillin Bridge and the Seattle areas unusual heavy concrete floating pontoon bridges as highlights.

Historic Bridges of Washington. The Pontoon Construction Project broke ground in February 2011 at a 55-acre site in Aberdeen Washington. The bridge opened in 1940 and sank in 1990 during a storm.

It is the second concrete pontoon floating bridge in Washingtons highway system and the worlds first floating pontoon bridge built over salt water subject to tides. Twenty- one of the pontoons that support the deck and superstructure are each 110 m x 23 m x 85 m and weigh 10000 tonnes. The bridge that crosses the Columbia at Wenatchee opened in 1908 and now 2011 used as a footbridge is the oldest extant steel cantilever bridge in the state of Washington.

Pontoon bridge The Evergreen Point Floating Bridge in Washington State carrying State Route 520 over Lake Washington seen from the north side bicycle and pedestrian trail from the west high rise. Some very deep low-frequency earthquakes can cause a seiche or a surface wave similar to a tsunami. There are two pontoon bridges for instance in Washington State that stretch across Lake Washington.

Washington State is noted for its unique collection of very unusual historic bridges. A conceptual image of the proposed pontoon. It features 77 concrete pontoons secured to.