Constructed under MassDOT's Accelerated Bridge Program, the $54-million Neponset River Bridge rehabilitation project was delivered by the project team in March, five months ahead of schedule. The project was split into two phases to better respond to traffic concerns. The 2,300-ft-long bridge carries more than 70,000 vehicles each day between Quincy and Boston.
The $20-million Phase 1 substructure rehabilitation contract, which started in August 2006, included complete reconstruction of deteriorated hammerhead pier caps and a seismic retrofit. The $34-million Phase 2 provided roadway deck reconstruction as well as improved access and safety for pedestrian traffic.
During Phase 1, the project required extensive temporary underpinning to support the superstructure while the pier hammerheads were reconstructed. J.F. White designed the underpinning and jacking system using a combination of heavy steel cribbing, transfer beams and tubular steel props to temporarily support the superstructure while demolishing and reconstructing the piers.
Phase 2 included extensive reconfiguration of pedestrian traffic, including Americans with Disabilities Act-compliant circulation across the bridge. New widened and accessible sidewalks were added to replace existing stair-only connections.
Neponset River Bridge, Boston
Owner Massachusetts Dept. of Transportation
Design Firm Dewberry
General Contractor J.F. White
Structural Engineer Simpson, Gumpertz and Heger
Surveying/Mapping Survey and Mapping Consultants