Structural Precast

Seattle Sound Transit

Project Outline

At a Glance

Industry: Segmental Bridge, Transportation, Light Rail
Market: Segmental Bridge
Services: Cast and Ship Precast Segmental Bridge System
Type of Facility: Bridge/Elevated Light Rail
Size: 2,500 pieces totaling for 5 miles of elevated sections
Time to Completion: 2 Years
Date Completed: 2007
Location: Seattle, WA

The Seattle Link is perhaps one of the most-used assets that the city offers to its growing population. Stretching for nearly 22 miles miles both underground and above-ground, the Link transports, on average, 84,376 people in, out, and around the city everyday. The Link serves not only as a mode of public transportation, but a well-known landmark throughout Seattle and its surrounding neighborhoods. Bethlehem Construction is proud to have been the precaster selected to build the precast segments that make up many of the elevated portions of this magnificent transportation system. Each segmental unit is cast against the previous one to ensure perfect fit and interlocking along the keyway. The undersides were parabolic for structural and aesthetic purposes and some portions required complex radius banked slopes.

When the units arrived on the jobsite they were craned into place with a trellis crane that spans pier to pier and lifts all the units at once. The segments are then interlocked in the air and cable is run through cast in ducts to post tension together. More than 5 total miles of eleveated sections were put in place that utilized over 2500 precast segmental units.