| 2000 Seventh Biennial Bridge Awards Competition
Eight Spans Honored in PCA Awards Program
Eight winners have been named in PCA's Seventh Biennial Bridge Awards Competition. This program was instituted in 1988 to recognize excellence in design and construction of concrete bridges. The 2000 program attracted 78 outstanding entries from Canada and the United States.All winning entries will receive an Award of Excellence at the American Concrete Institute Awards Breakfast, to be held in March 2001 in Philadelphia.
The winning bridges, without regard to catagory or ranking, are
listed below. For a larger view of a bridge, click on the thumbnail
photograph that accompanies the text.
Gorge Bridge, Ogden Scenic Wayside, Terrebonne, Oregon
profile of the bridge was a primary element of design for this 410-ft
(125 m) arch bridge spanning a 300-ft (91.4 m) deep scenic Crooked
River gorge. Spanning the deep gorge was accomplished by utilizing
a unique method of construction, employed for the first time in
the United States. The arch was constructed using a cast-in-place
segmental method while the already completed portions of the arch
were supported by temporary towers and stay cables. The slender
arch's rib begins with 6 ft 6 in. (2 m) depth at the springing,
tapering to 4 ft (1.2 m) at thecrown. The width of the arch is 43
ft (13.1 m), whereas the roadway deck is 79 ft (24.1 m) wide. Each
of the large deck overhangs is supported by tapering the outside
cell of the box-girder deck.
Principals: Oregon Department of Transportation, owner;
David Goodyear Engineering Services, engineer; Kiewit Pacific, contractor;
and Quality Materials Inc., concrete supplier.
Jury Comments: A wise choice of an efficient structural form
to span the canyon. The visual profile matches the location and
appearance of the adjacent structures. The innovative construction
technique resulted in a very economical solution.
Highway Reconstruction Salt Lake City, Utah
bridge demonstrates the superior structural efficiency of the Utah
Metric Segmental Post Tensioned Girders used for a single point
urban interchange with a clear span requirement of 230 ft (70.1
m). The selection of the precast system over other options was based
on the advantages it afforded: design freedom, longer spans, higher
quality, speed of construction, and economy.
Project Principals: Utah Department of Transportation, owner;
Sverdrup Civil and Parsons Transportation Group, engineers; Wasatch
Constructors, contractor; Basic Precast Company, concrete supplier;
and Basic Precast Company, precaster.
Jury Comments: This bridge exemplifies the good use of high-performance,
high-strength concrete to extend the span capability of prestressed
Avenue Bridge Columbus, Ohio
Community involvement and careful attention to architectural details
were very important considerations in this bridge project. The five
elegant precast, prestressed skipping arches mimic the historic,
earth-filled, concrete arch bridge being replaced. Use of concrete
played a vital role in achieving the desired aesthetic appeal. Architectural
treatments included formliners for the superstructure and substructure
elements to replicate stone appearance and texture, light posts,
handrail posts, and traffic barriers. To preserve the investment
of the valuable community involvement, the bridge was designed for
a service life in excess of 100 years.
Principals: Franklin County, Ohio, owner; HNTB Corporation,
and Eriksson Engineering, engineers; HNTB Corporation, architect;
C.J. Mahan Construction, contractor; Anderson Concrete Corporation,
concrete supplier; and Tecspan Concrete Structures, Inc., precaster.
Jury Comments: A classic arch bridge in a classic material.
Concrete played a vital role in meeting the values of the community
by replicating the aesthetics of the replaced bridge.
Vegas Spaghetti Bowl Las Vegas, Nevada
This is the largest highway project in Nevada's history. The $93
million Spaghetti Bowl Interchange contract was the largest single
construction contract ever let by NDOT. The project includes four
segmental bridge ramps, worth $43 million, with spans ranging from
100 ft (30.5 m) to 212 ft (64.6 m). The tight spiraling geometry
of the ramps with radii as small as 427 ft (130.1 m), quickly earned
the name "Spaghetti Bowl" for this urban interchange. Fast construction,
ability to handle tight curvatures, minimal disruption to traffic
during construction, and economy were the reasons for selecting
the concrete precast segmental construction, the first for NDOT.
Employing innovative management techniques, the project was completed
six months ahead of schedule and within budget
Project Principals: Nevada Department of Transportation,
owner; Parsons, Brinkerhoff, Quade and Douglas, Inc., Figg Engineers,
and Finley-McNary Engineers, Inc., engineers; Meadow Valley, and
Walter SCI, contractors; Ready Mix Inc., CSR, and Nevada Ready Mix,
concrete suppliers; and Walter SCI, precaster.
Jury Comments: The success of this project
is a testament to the importance of the proper selection of materials,
construction methods, and the partnering between the owner, engineers,
contractor, and the community.
Screwtail Bridge Sunflower, Arizona
This concrete site-cast, post-tensioned, balanced cantilever segmental
bridge is the first of its kind for Arizona. The structure type
was chosen because it would have the least impact on the environmentally
sensitive riparian area and the historic pioneer roads located within
the footprint of the bridge. Designers of this four-span structure
with a maximum span of 405 ft (123.4) paid particular attention
to various structural and architectural issues. High performance
concrete was specifically designed to combat the harsh desert environment.
By using structural concrete, the team was able to design a bridge
with long spans, slender piers, parabolic geometry, and a subtle
color so that the bridge blends seamlessly with the surrounding
desert; while being economical at the same time.
Principals: Arizona Department of Transportation, owner;
T.Y. Lin International, engineer; Ames/Edward Kraemer & Sons, Inc.,
contractor; and United Metro, concrete supplier.
Simple in form, and architecturally elegant, this bridge blends
with the surrounding desert while respecting the environmental needs
of the site.
Circle West Vehicular Bridge Forest Park, St. Louis, Missouri
The challenge for the design of this simple 44-ft (13.4 m) span
crossing a river was to create a formal look complementing the English
garden landscaping and the elegant look of the music bandstand located
in the famous Forest Park in St. Louis. The architects vision of
the bridge coming out of the water, was achieved by clever use of
curved precast infill wall panels for this simple, 44-ft 4-in long,
precast, modular, arch bridge. All exposed concrete was pigmented
to match the Indiana limestone that is used on adjacent structures.
Project Principals: City of St. Louis, Board of Public Service,
owner; David Mason & Associates, St. Louis Development Corporation,
URS/O'Brien-Kreitzberg, and CON/SPAN Bridge Systems, engineers;
David Mason & Associates, architect; Schuster Engineering, Inc.,
contractor; Egyptian Concrete Co., concrete supplier; and Egyptian
Concrete Co., precaster.
Comments: It is a marvelous design for a simple box culvert
that is engineered to facilitate construction. The use of fascia
panels contributes to the bridge's beauty yet maintains the simplicity
of the structure.
Cart Bridges Rancho Santa Fe, California
to span two 285-ft (86.9 m) wide and 75-ft (22.9 m) deep canyons,
these two stressed-ribbon bridges are on the most exclusive golf
course in San Diego county. The bridges' sag-vertical curve and
unusually thin section depth are striking to the viewer. The upside-down
fixed arch structures' construction begins with stringing bare prestressing
cables from one abutment to the other. Next, precast deck panels
are hung creating a structure similar to a string of beads. Cast-in-place
closure pours between panels forms a continuous deck. The tension
caused by applied loads in this catenary-shaped structure, is offset
by introducing a pre-compression by stressing a second set of prestressing
strands placed within the deck panels. This innovative construction
technique was chosen to reduce cost, save construction time, and
minimize impact in an environmentally sensitive area.
Principals: Lennar Communities, Inc., owner; T.Y. Lin International
and AGRA Earth & Environmental, engineers; FCI Constructors, Inc.,
contractor; Palomar Transit Mix, concrete supplier, and San Diego
Comments: It's a one-of-a-kind in the U.S., designed for pedestrians
as well as for light vehicles. The designers overcame environmental
challenges with this very long span bridge built without any falsework,
Access Project, Portage Creek Bridge Portage, Alaska
This 3-span, precast, prestressed, decked bulb-tee bridge provides
the first highway access for travel, tourism, commerce, and emergency
services to the City of Whittier, and the majestic Prince William
Sound. The bridge was designed to meet a broad range of architectural,
engineering, and environmental criteria including seismic, soil
liquefaction, aesthetics, constructability, environmental sensitivity,
and cost. With the help of a computer, a visual impact analysis
was performed regarding the "near-view" and "far-view" of various
design options. When this was coupled with structural design requirements
for very high seismic loads, single-column hammerhead piers was
the solution. To deal with a short construction season and the ambitious
project schedule, the owner used an innovative contracting arrangement
and awarded a separate contract for the design and fabrication of
the prestressed girders, well in advance of the main construction
Principals: Alaska Department of Transportation and Public Facilities,
owner; CH2M Hill, engineer; Land Design North, architect; Herndon
and Thompson, Inc., Sandstrom & Son, Inc., and Agra Foundations,
Inc., contractors; Davis Concrete, concrete supplier; and Aggregate
Products, Inc., precaster.
Comments: Simple yet impressive. With conscious efforts to assess
the visual impact to the surroundings, and solid engineering, the
designers have achieved a careful balance of aesthetics, engineering,