Naylor Road Station and Aerial Structure
Prince Georges County, Maryland
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Naylor Road Station
 The
Naylor Road Station and Aerial Structure along the Washington Metropolitan
Area Transportation Authority (WMATA) Green Line in Prince Georges
County, Maryland, is a graceful, cost-effective, and functional
structure that further expands this impressive transit system.
The Green Line project, including an aerial structure and station,
was constructed in the last phase of the WMATA 103-mile fast-track
construction program, and extends about 1.2 miles. About 0.75 miles
of this section consists of a continuous-span aerial structure made
from externally post-tensioned precast concrete segmental box girders
using separate box units for inbound and outbound tracks. The remaining
portion of the line is constructed at grade. The station canopy
and the post-tensioned aerial structures were built with cast-in-place
concrete. The structure is supported on cast-in-place concrete piers
and abutments with precast concrete pile foundations.
After considering several design options, the engineering firm
of Whitman, Requardt & Associates chose to use 10-foot-long
precast segments with external post-tensioning continuous over supports.
 Other
design features were match-casting of precast segments, deck slabs
to support a concentrated load of 15,000 pounds anywhere along the
slab (train derailment load), no tension stress on the bridge, a
special provision to permit future addition of external tendons,
provision for adequate drainage inside the bow girders and other
confined spaces where water would collect, and provision for future
bearing replacement.
A value engineering redesign was performed by Finley McNary Engineers,
Inc. (FME), for the superstructure. FME overcame geotechnical constraints
and proposed the use of an overhead erection truss system, saving
WMATA over $250,000 and enabling rapid construction of this complex
structure with minimal disruption to several busy thoroughfares.
The completed project cost approximately $28 million and is a striking
addition to the WMATA Green Line and the community.
Project Credits
Owner: Washington Metropolitan Area Transit Authority
Engineer: Whitman, Requardt & Associates / ABAM
Architect: Victor Wilburn Associates
Contractor: The Lane Construction Corporation
Concrete Supplier: Opportunity Concrete Company
Precaster: Bayshore Concrete Products
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