Concrete Bridge Case Study
Bridges Home
> High Performance Concrete > Power Road/CAP
Canal Overpass Bridges
Innovative Concrete Bridge Overcomes The Obstacles
 The
Red Mountain Freeway Power Road/CAP Canal Overpass Bridges in Phoenix,
Arizona use innovative designs to cross both a six-lane highway
and a canal that serves as a major link in Arizona’s water
supply. These designs allowed for a concrete structure to be constructed
rather than a more expensive curved welded plate girder structural
steel bridge.
 Both
the highway (Power Road) and the Central Arizona Project (CAP) canal
intersect the Red Mountain Freeway Bridges at skews. Yet the designers
were able to eliminate the significant bridge skews by using outrigger
straddle bents at Power Road and precast straddle assemblies at
the CAP canal crossing.
 The
girders for the bridges were precast, pretensioned AASHTO Type V
and Type VI concrete girders. The piers and post-tensioned straddle
bents and assemblies used cast-in-place concrete and on-site precast
concrete. The aesthetic coloring of the structure was chosen to
match the surrounding environment.
More information on these bridges can be found in the article by
the designers of the bridge: Beck, N. Dillon and Shiosaka, Daniel
R,. “Normal But Not Ordinary,“ Civil Engineering,
Vol. 78, No. 7, July 2008, pp. 52-61.
|