MassDOT’s Commonwealth Avenue Bridge Reconstruction Project will replace the existing superstructure (concrete deck and steel beams), or the “deck”, that carries Commonwealth Avenue and the MBTA Green Line B Branch over the Massachusetts Turnpike and MBTA Commuter Rail line.
The existing superstructure consists of three independent, longitudinal sections:
- Commonwealth Avenue heading east
- MBTA Green Line B Branch
- Commonwealth Avenue heading west
Constructed circa 1965, the bridge superstructure is in poor condition and in need of replacement. The project will replace the entire superstructure of the bridge and incorporates a number of functional and safety improvements, including improved pedestrian access and signaling, new articulated bike lanes, and better MBTA bus pick up and drop off accommodations. The width of the bridge superstructure will be approximately the same as it is today, and its vertical profile will be similar to avoid other impacts. The substructure below the Commonwealth Avenue deck was replaced in 2015.
Accelerated Bridge Construction (ABC) methods will be used on this project to shorten the duration of on-site construction time. Conventional bridge replacement techniques would have extended construction four to five years and would have resulted in greater traffic and transit impacts. Using ABC strategies, MassDOT will employ multiple crews working on a 24/7 basis to remove and replace the existing bridge, while maintaining traffic flow on the Massachusetts Turnpike below with lane reductions. The construction management team, led by Walsh Construction Co., will use precast concrete elements and rapid-set concrete and will construct the deck panels off-site for positioning when needed. The construction team will work in continuous shifts during the intensive construction periods listed below. More detailed information about impacts during construction, as provided by the MassDOT, can be found on the project schedule page.
Project Schedule Highlights
July 27 – August 14: Eastbound side of Commonwealth Avenue along with Green Line MBTA area were completed.
July 26 — August 11: Westbound side of Commonwealth Avenue.