Broadway Bridge

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The Broadway Bridge is a double leaf Rall Bascule lift bridge across the Willamette River that connects NE Broadway and NW Broadway.
View from the Broadway Bridge.
It was built in 1912, rehabilitated in 1927, and has average daily traffic of 29,000. [1]

History

The Broadway Bridge was constructed between 1911 and 1912, opening on April 22, 1913. In 2010, it was shutdown for several months while Portland Streetcar tracks were installed as part of the streetcar's Eastside expansion.

Bridge Design

The length of the largest span is 304.1 ft, total length is 1,742.2 ft, deck width is 45.6 ft and vertical clearance above deck is 13.1 ft. [1] The bridge is a double leaf bascule (which means seesaw in French) making it a very complicated drawbridge and is one of the reasons why the Broadway Bridge openings can take 20 minutes or longer (versus 5 to 8 minutes for the Burnside Bridge, Morrison Bridge, and Hawthorne Bridge). The weight of the deck (the leaf) is balanced by a counterweight, of which their are two located above the bridge's deck. The bascale span for this bridge was invented by Theodore Rall, thus the name Rall Bascule. Each leaf, which measure about 140 ft and weigh 2,000 tons, and its counterweight roll back and forth on giant bull wheels to allow maximum river clearance. [2]
The bridge was designed by Ralph Modjeski of Chicago, Il and the bascule span was designed by the Strobel Engineering Company of Chicago, who holds the Rall patent. The Union Bridge and Construction Co. of Kansas City, Mo constructed the substructure and the Pennsylvania Steel Co. of Steelton, PA fabricated and erected the steel and bascule spans. In 1927 Gustav Lindenthal of New York designed part of the Lovejoy Street ramp as well as modifications to the truss spans. [2]

References