SH58 Ramp A Flyover Bridge

Golden, Colo.

This Colorado ramp flyover bridge is unique both for its use of state-of-the-art curved precast concrete girders and for the difficult, busy traffic thoroughfares over which it was built. All traffic crossings were high-volume roadways that required night and weekend erection and lane closures. The bridge currently has the longest span using constant-depth precast U-girder construction in Colorado. It employs a number of innovations and refinements of this type of construction, which demonstrates the flexibility inherent in the use of precast U-girders. The bridge's design blends the advantages of cast-in-place concrete construction—for example, post-tensioning, torsional rigidity, and the ability to accommodate complex geometrics—with the quality of plant fabrication and cost effectiveness of using standard, predictable cross sections. By expanding the application of precast concrete to projects that involve complex, curved geometry and long-span structural design, the many advantages of using precast concrete products can be readily proven and eventually expanded to new markets.

Precaster: Encon Bridge Co. LLC, Denver, Colo.
Website: www.enconcolorado.net

Engineer of record: CH2M Hill, Englewood, Colo.
Website: www.ch2m.com

Engineer of record: Summit Engineering Group, Inc., Littleton, Colo.
Website: www.summit-eng-group.com/index.cfm

Deck area: 80,375 ft²
Bridge length: 2115 ft
Bridge longest span: 580 ft
Bridge width: 38 ft
Precast concrete components:
38 modified CDOT U84 girders
265 prestressed precast concrete panels between girders
166 prestressed precast concrete deck panels between girder webs