Long Span Bridges & Vibrations
Full Session with Abstracts
343155-1 - Clearfork Main Street Bridge – Two Bridges in One
Saturday, April 21
8:00 AM - 9:30 AM
Challenged by competing demands of limited budget, stringent flood control requirements, urban pedestrian trail connectivity, and an emphasis on bridge aesthetics, the Clearfork Main Street Bridge employed a concrete spliced girder system (the second in Texas and the first in 25 years) with a unique steel pedestrian bridge suspended below.
The vehicular bridge is composed of five beam segments spliced together with post-tensioning tendons to form one continuous three-span girder with a center span of 220 feet. Spliced girders combine the economy and durability of precast concrete beams with the long span capabilities and aesthetics of a continuous steel girder. The girder segments were constructed of readily available precast beam shapes, haunched at the columns for additional strength and reduced live load deflection.
As a more direct way to allow pedestrian trail users to cross the river, the team designed a trail–level pedestrian bridge suspended below the vehicular level. This pedestrian level connects to the two river banks at trail level, offering a shorter, shaded trip separate from the motor vehicle traffic. The pedestrian bridge is supported by tension-only hanger rods and, at midspan only, a set of steel pipe hangers to ensure enough torsional rigidity to prevent dangerous wind-excited bridge oscillations.
At each end of the pedestrian bridge, near the vehicular bridge abutments, the team designed plaza areas that serve as multi-nodal trail connections with tiered seat walls offering a shaded rest area for pedestrians and cyclists. The bridge abutments act as a canvas for large scale public artworks measuring 30 feet wide. These plazas, with their shaded seating and attractive public art, transform what is normally a neglected space to one that is a pedestrian refuge.
This presentation is targeted to a national audience of bridge design professionals