Transportation difficulties, elimination of the center pier and environmental restraints presented a major design-construction challenge for this nearly 200 ft (61 m) long bridge in a mountainous region of Washington State. The solution was to divide the girder into three 63 ft (19.2 m) pretensioned bulb-tee girder segments and transport them 150 miles (240 km) to a staging area near the bridge site. There, he segments were spliced and post-tensioned to give a total girder length of 190 ft 6 in. (58.1 m). The girders were then hauled to the bridge site where they were guided into position with a launching truss and two cranes. Construction time took only 31/2 months. This article discusses the project constraints, structural design, production, transportation, splicing and fina l erection. The highlights of the project are narrated from the perspective of the structural designer and precaster.
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