MBTA Bus Tunnel / Fort Point Channel
HEIGHT: 7.77m (23’-3’)
WIDTH: 11.28m (37’-0”)
TOTAL IMMERSED LENGTH: 210 m
DEPTH AT BOTTOM OF STRUCTURE: Depth below sea level .approx. 15 m
ENVIRONMENTAL CONDITIONS:
Contaminated soil in the bottom of the channel necessitated the use of the sheet piling to limit
the amount of contaminated soil to be disposed of.
Organic clay & till overlying glacial rock.
FABRICATION METHOD:
Tunnel sections were fabricated in a nearby, World War II-era
dry dock
WIDTH: 11.28m (37’-0”)
TOTAL IMMERSED LENGTH: 210 m
DEPTH AT BOTTOM OF STRUCTURE: Depth below sea level .approx. 15 m
ENVIRONMENTAL CONDITIONS:
Contaminated soil in the bottom of the channel necessitated the use of the sheet piling to limit
the amount of contaminated soil to be disposed of.
Organic clay & till overlying glacial rock.
FABRICATION METHOD:
Tunnel sections were fabricated in a nearby, World War II-era
dry dock
Boston, MA,
United States
MBTA
Modern Continental Construction Co. Inc.
Jenny Engineering Corporation
71m
210m
15m
Project construction
2004-04-30
3
2-cell rectangular box
7.77m
11.28m
Dredged excavation supported by cantilevered sheet piles. Elements immersed within sheet
pile cofferdam.
pile cofferdam.
Tunnel sections were fabricated in a nearby, World War II-era
dry dock
dry dock
NA
Contaminated soil in the bottom of the channel necessitated the use of the sheet piling to limit
the amount of contaminated soil to be disposed of.
Organic clay & till overlying glacial rock.
the amount of contaminated soil to be disposed of.
Organic clay & till overlying glacial rock.
Lay barge
Gina/Omega Gaskets
Steel plates on the bottom slab and two ply spray on membrane on the walls and top slab.
The tubes will sit on hydraulic pin-jack foundations. Once set to grade, sand was pumped under
the tubes. Underlying material is clay.
the tubes. Underlying material is clay.
Ordinary Backfill
Regular - 4000 psi
1.1