Title:
Immersed-Tube Concrete Tunnel
Sweeps Across Baltimore Harbor
Author(s):
Scott S. Pickard
Publication:
Concrete International
Volume:
2
Issue:
12
Appears on pages(s):
40-48
Keywords:
concrete construction; cylindrical shells;
highways; interstate highway system; joints (junc-tions);
prefabrication; tremie concrete; tunneling (ex-cavation);
DOI:
Date:
12/1/1980
Abstract:
The construction of the 8800.ft (2682-m) Fort McHenry Tunnel across the inner harbor in Baltimore City will connect the final remaining gap in Interstate 95 in Maryland. The 5400 ft (1646 m) underwater portion of the tunnel will be constructed with 16 pairs of prefabricated steel-shelled concrete tunnel elements (tubes), each pair of tunnel elements placed side-by-side in the same trench only 10 ft (3 m) apart. Each tunnel element contains two bores which carry two lanes of traffic each, giving a total of eight lanes of traffic. A typical tunnel element, which is 350 ft (107 m) long, 82 l/2 ft (25 m) wide, and 42 ft (13 m) high, will be built on inclined ways in a shipyard, side launched and towed to the site, lowered into position by a special catamaran-type barge, and joined to adjacent tunnel elements with a rubber gasket seal or tremie concrete joint. [Author]