Crooked River Bridge - Terrebonne, Ore.
The Crooked River Gorge Bridge is the country's first segmentally cast, temporarily cable-stayed, single-span arch bridge. Kiewit used a construction methodology rarely found in the United States. Divided into 15 separate segments, the bridge was built without the use of typical falsework. Stretching 535 feet across the Crooked River 295 feet below, the bridge is four lanes wide with a center median and accommodates 10,000 vehicles per day.
The first step during construction was providing support for the concrete arch. A self-advancing traveler form was used to place the concrete. The mix was highly specialized and had to reach 4,350 psi within 48 hours of the pour to enable the traveler to move forward in preparation of the next pour. Temporary cable stays were used to support the arch while under construction. The arch was completed in September 1999, and work immediately began on the superstructure for the roadway deck.
Superstructure construction had to be completed in a specific sequence due to the arch's sensitivity to applied loads. Concrete work on the roadway deck began in March 2000, following the same sequencing protocol. The bridge opened for use on September 16, 2000.