Civil
engineering is perhaps the broadest of the engineering fields, for it
deals with the creation, improvement, and protection of the communal
environment, providing facilities for living, industry and
transportation, including large buildings, roads, bridges, canals,
railroad lines, airports, water-supply systems, dams, irrigation,
harbors, docks, aqueducts, tunnels, and other engineered
constructions. McNally Group provides premier technical, management,
and directly related services to develop, manage, engineer, build
complicated civil structures.
For
more information info@mcnallytunneling.com
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Some
of the ground conditions and techniques have included:
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Machine Mining
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Soft ground
tunnel boring machines
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Earth pressure
balanced (EPB)
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Soft ground in compressed air
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Micro tunneling
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Rock tunnel boring machine
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Rock excavation using road header s
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Hand Mining
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Soft ground in free air
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Soft ground in compressed air
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Conventional drill and blast
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Various Structures, above and
underground
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Outfall Structures
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Flow Control Structures
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Gate/Valve Houses
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Overflow Chambers
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Creating Solutions...
Recognizing the need for improved tunnel
lining technology, NASCO (North American Segment Company) was
formed to manufacture precast tunnel segmental linings.
The First linings were produced for the Alki
Transfer Tunnel in West Seattle. The lining is made of 9 inch
thick precast concrete (6000 psi) segments bolted together to
form a single pass, smooth wall tunnel 133 inches internal
diameter.
Precast Tunneling Segmental Linings. Alki Transfer Tunnel,
Seattle, Washington 1996
When assembled the trapezoidal shaped segments
form a bolted ring that when measured along the tunnel is 43.5
inches on one side and 40.5 inches on the other (42 inches
Nominal). This difference in length is known as a taper and by
rotating consecutive rings the variations in tunnel alignment
and grade can be attained. Using a trapezoidal tunnel segment
lining requires no special rings or key pieces as all rings
are identical
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The McNally
Group has expertise in many types of Civil and Transportation
related engineering projects.
As in tunnel
construction, understanding the needs of the client and the
public-at-large are essential to the successful completion of
a project.
The tunnels
which we have constructed vary in size from a 27-inch diameter
micro tunneling project to a 30-foot diameter water intake
tunnel varying in lengths of several hundred feet to several
miles.
As growth in
urban areas continues, underground construction using
specialized tunneling methods minimizes surface
disruptions.
Our expertise in
tunneling projects include:
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Hydro electric
generation
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Water intake
and discharge
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Storm and
sanitary sewers
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High pressure
water mains
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Pedestrian and
vehicular traffic
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Communication
and power transmission
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Transit and
railway systems
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Gas
transmission
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Mine conveyor
and access
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McNALLY
TUNNELING CORPORATION 
