The $ 3.9 million expansion from the bridge of the bridge of Hampton Roads in Virginia reached another milestone on September 24, as the boring machine of the Mary tunnel broke a retaining wall to complete a second 46 -foot tube, 7,900 feet in length, which will end up adding a very necessary capacity for congested crossing.
Named Mathematics and Engineer Mary Winston Jackson, who was performed in the movie “Hidden Figures”, the 430 -foot variable tunnel machine in length 4,700 tonnes began its return trip in April 2023, completing the first tube less than a year later. After an intricate return process through nitrogen table technology and routine maintenance, Mary began to bore the second tunnel last October.
According to the Virginia Department of Transportation, Mary moved a total of more than a million highly compressed clay and clay clusters on a 3 -mile round trip, which spread more than 100 feet below the river bed and up to 173 feet below the medium level. The Agency states that Mary set a world productivity record for his TBM/TBM size class, bored 366 feet in one week.
Along the way, Mary installed about 2,400 tunnel rings composed for approximately 21,600 prefabricated segments. The TBM had its trip to “Katherine”, a slurry treatment plant of 92,500 square meters, named for the NASA colleague of Jackson, Katherine Johnson, with a flow capacity of 13,200 GPM, the largest in North America, according to VDOT.
In parallel with a pair of two -lane tunnels, opened in 1957 and 1976, the new tubes were part of the largest road construction project in Vdot. Hampton Roads Connector Partners (HRCP) – a joint Dragados design company USA, Vinci, Dodin Camenon Bernard and FlatIRON builders – is also building 17,000 feet of new and up -to -date sea disorders that will expand the four to eight lanes crossing a better daily traffic accommodation that can exceed 100,000 vehicles during the summer months.
Two lanes in each direction will bring a general purpose traffic, with the other two designated as express lanes, with revenue for operations, maintenance and finance other region infrastructure projects.
Although Mary’s head is out of the tunnel, VDOT claims that the TBM still has five rings to be installed before it can be dismantled, a process that will be expected to begin in November after the removal of the slurry treatment plant. HRCP will now continue with the inner creation of the two tunnels.
VDOT says that the project, which began in 2020 and also includes 25 new and rebuilt bridges and incorporations of road capacity on the sides of Hampton and Norfolk of the port, has continued on the path from the “forced cost impacts and programs” forced “forced” a In early 2014, reset its integral agreement with HRCP. This movement added 18 months to the original end goal of 2025, with a substantial completion now established for February 2027.
