The Denver Millennium Bridge is the world's first

cable-stayed bridge A cable-stayed bridge has one or more ''towers'' (or ''pylons''), from which cables support the bridge deck. A distinctive feature are the cables or stays, which run directly from the tower to the deck, normally forming a fan-like pattern ...

using post-tensioned structural construction. Its 200-foot (61 m) white tapered steel mast rises above

Denver Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the Unit ...

's northwestern skyline, connected to the bridge deck and foundation anchored by steel cables. The

footbridge A footbridge (also a pedestrian bridge, pedestrian overpass, or pedestrian overcrossing) is a bridge designed solely for pedestrians.''Oxford English Dictionary'' While the primary meaning for a bridge is a structure which links "two points at ...

crosses

railroad Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prep ...

tracks and the regional light rail system, climbing no higher than 25 feet (8 m) above street level, thereby minimizing the height pedestrians must climb. Located near

LoDo LoDo (Lower Downtown) is an unofficial neighborhood in Denver, Colorado, and is one of the oldest places of settlement in the city. It is a mixed-use historic district, known for its nightlife, and serves as an example of success in urban reinves ...

(Denver's lower downtown), in Riverfront Park, the Millennium Bridge connects the popular

16th Street Mall The 16th Street Mall is a pedestrian and transit mall in Denver, Colorado. The mall, 1.25 miles (2 kilometers) long, runs along 16th Street in downtown Denver, from Wewatta Street (at Union Station) to the intersection of 16th Avenue and Broad ...

with the Commons Park in the Central Platte Valley District of the Union Station neighborhood. The bridge is the first of three pedestrian bridges between

Downtown Denver Downtown Denver is the main financial, commercial, business, and entertainment district in Denver, Colorado. There is over of office space in downtown Denver, with 132,000 workers. The downtown area consists mostly of the neighborhoods of Uni ...

and the Highland neighborhood.

Design

The name, Denver Millennium Bridge, honors a milestone in time and in Denver's architectural development. To meet the structural challenge of spanning 130 feet (40 m) without a steep increase in elevation, the deck's structure must be as thin as possible while remaining stable. This cable-stayed bridge uses a steel frame that derives its stiffness from tension by using a single mast that is tilted toward one end of the bridge. Cables supporting the bridge deck are welded to both sides of the mast, but cable to foundation anchors attach to the mast only from the side of the bridge toward which the mast is tilted. Supportive tension is created by using the mast as a lever to pull the deck up into a shallow arc, keeping the opposite end of the bridge secured by two steel rods. With the mast raised,

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wid ...

was poured onto the metal deck frame, pushing the deck into place and applying tension to the cables. The post-tensioned structural construction allows for a substantially thinner 6-inch-thick reinforced concrete slab-on-metal deck. The deck structure is supported by secondary I-Beams, and has an average width of 80 feet (24 m).

History

Preliminary work on the $9-million

began in 1999. The structural and civil

engineering Engineering is the use of scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad range of more speciali ...

firm Ove Arup & Partners, in conjunction with the

architectural Architecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing buildings o ...

design company ArchitectureDenver, developed the design. Contractor Edward Kraemer & Sons, Inc. implemented the design, subcontracting Colorado Bridge and Iron to fabricate the steel components. The mast was constructed of cone-shaped steel plate sections welded together to form a 3-foot (1 m) base, 7-foot (2 m) midsection and 1.5-foot (.5 m) tip diameter. Glass-enclosed

elevator An elevator or lift is a cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or decks of a building, vessel, or other structure. They ...

towers on both ends of the footbridge accommodate pedestrians who have difficulty climbing the stairs leading up to either end of the bridge from street level. The Millennium Bridge was completed and officially opened by Denver Mayor

Wellington Webb Wellington E. Webb (born February 17, 1941) is an American politician. He served in the Colorado House of Representatives and was the first African American mayor of Denver, Colorado, serving from 1991 to 2003. Early life and career The Webb fam ...

on April 22, 2002. On April 24, 2014, a $1-million renovation began on the

to increase pedestrian accessibility to the bridge, which allows for smoother access between downtown Denver and the Central Platte Valley and Lower Highlands neighborhoods. Part of this renovation includes modifications to the east staircase and an upgrade to LED lighting, which will allow for the colors to be changed and increase energy efficiency by up to 80%.

Awards

*2002 Urban Design Merit Award, Denver Chapter American Institute of Architects *Gold Award, New York Association of Consulting Engineers "Engineering Excellence Awards 2003"

Photo gallery

References

*Wagner, Ho
“Millennium Bridge Rising in Denver’s Central Platte Valley”, ''Rocky Mountain Construction''
(August 27, 2001)
“Mast-Raising Creates New Denver Landmark”
(June 22, 2001) Colorado Construction—Newswatch

Denver Museum of Nature & Science
“Raising the Mast on Denver Millennium Bridge”
(July 27, 2001) Arup
“Denver Millennium Bridge Opens”
(April 26, 2002) Arup
“Standout Mast is up on Denver Millennium Bridge”
(June 25, 2001) Arup *Collis, Hugh (September 2003) "Denver Millennium Bridge, Colorado, USA 1999 - 2002" ''Transport, Engineering and Architecture''. Burlington, MA: Architectural Press. {{ISBN, 0-7506-7748-1 *Eddy, John "Denver Millennium Bridge", ''The Arup Journal'', 2003, n. 1 v. 38 . Cable-stayed bridges in the United States Pedestrian bridges in Colorado Towers in Colorado Transportation buildings and structures in Denver Buildings and structures celebrating the third millennium Steel bridges in the United States

Design

History

See also

Awards

Photo gallery

References