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the alignment had to thread through so in the area below the bridge, this feature Extremely efficient design practices
many businesses, a curved steel bridge will be an even larger success. encouraged high-quality results without
structure was necessary. This resulted unnecessary spending. The project team
in a much more challenging design and The extension bridge is multimodal, worked closely with stakeholders to
construction than a standard concrete accommodating not just vehicles but ensure that all project goals were met,
beam bridge. Compared to standard also bicyclists and pedestrians, many holding stakeholder meetings once
concrete beam bridges, steel bridges are of whom arrive by Greyhound bus per month as well as several meetings
more difficult to design and construct. at the station a few feet away. In an each month between the client, design
And typical for most curved girder innovative application of Complete team and consultants. The resulting
bridges, Division Street caused increased Streets theory, designers used colored project exceeded the client’s needs
torsional forces and displacements, concrete to differentiate designated bike and expectations for budget, time and
differential deflections and girder flange paths. Colored concrete has become design.
lateral bending. A bearing design for the increasingly popular as a durable method
bridge was also needed to accommodate for visually separating crosswalks from The Division Street extension bridge
displacement and girder end rotations. roadways, and the same theory works has also already begun to encourage
These challenges created bigger and well for bike paths, helping keep drivers growth and expansion between the
subsequently more costly member sizes and cyclists safely in their respective Gulch and SoBro neighborhoods in
in the cross frames, girder flanges and lanes. To incorporate another creative the six months it has been open to the
bearings. use of technology, designers embedded public. Several properties along the
LED delineator lights between the corridor are being redeveloped, and
In an effort to reduce fabrication costs, bicycle and pedestrian pathways to other projects are in the pipeline. As fate
the team applied an innovative solution: provide safe lighting while minimizing would have it, the project even connects
locating field splices at the beginning and environmental impact. the Gulch to the Howard School campus,
end of the horizontal curve. This allowed a location of several Metro offices. City
for the fabrication of tangent girder The project is also fully in line with employees are enjoying being able to bike
sections at the beginning of the bridge the City’s Green Streets initiative to work from the Gulch, thus reducing
with the curved portion located between and particularly focuses on limiting congestion on nearby streets.
the field splices. This was a tremendous stormwater runoff and pollution. In
benefit to both the girder erection and keeping with Complete Streets practices This project is another step in the
fabrication. Additionally, the girder and sustainable design principles, the direction of helping Nashville achieve
framing was radial, which allowed for design team made the decision to slightly its ambitious goal of becoming one
standardization of the cross frames. narrow the street from 12 feet to 11 feet of the greenest cities in the country.
and 10 feet, in an effort to control traffic The extension bridge has played and
To further support community buy-in, flow and minimize impervious asphalt will continue to play a leading role
the team proposed a pedestrian path surfaces. Curb cuts direct stormwater to in redefining current thinking in the
from the bridge level down to the street rain gardens and bioswales, which filter Nashville region regarding Complete
below. The path helped to make the runoff through planting and engineered Streets and sustainable street design. It
project more worthwhile for the street- soil layers, minimizing the amount was highly anticipated by the public and,
level businesses, including a restaurant of street pollution entering tributary as a result, became a very visible example
and a bar, affected during construction. systems. of how engineering can advance positive
Now that the bridge is complete, change in a community. Its success has
residents and visitors of the affluent Given the social and economic put Complete Streets at the center of city
Gulch district can reach these businesses importance of this new connector, the infrastructure discussions and illustrated
with a 10-minute walk, bringing extra City of Nashville was determined to the power of transportation projects to
appetites and deeper pockets to their build not just another overpass, but connect communities and contribute to
front door. As more businesses develop a street that truly supports all users major quality-of-life improvements.
and the larger goals of the community.
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