Limfjord Tunnel
TOTAL IMMERSED LENGTH: 510 m
DEPTH AT BOTTOM OF STRUCTURE: 20.8 m
HEIGHT: 8.54 m
WIDTH: 27.4 m
FABRICATION METHOD: Cast in a casting basin excavated for the purpose, about 10 km from the tunnel site. Elements were cast in 12.8 m long sections - first the bottom; then the walls; and, last, the roof. The sections were separated by a 1.8 m gap into which rebars protruded. These gaps were filled after concrete shrinkage had taken place
DEPTH AT BOTTOM OF STRUCTURE: 20.8 m
HEIGHT: 8.54 m
WIDTH: 27.4 m
FABRICATION METHOD: Cast in a casting basin excavated for the purpose, about 10 km from the tunnel site. Elements were cast in 12.8 m long sections - first the bottom; then the walls; and, last, the roof. The sections were separated by a 1.8 m gap into which rebars protruded. These gaps were filled after concrete shrinkage had taken place
Aalborg,
Denmark
Ministry of Public Works
The tunnel elements by NYBYG; approaches by Monberg & Thorsen A/S; Christiani & Nielsen A/S carried out the installation of the elements, including sandjetting.
Christiani & Nielsen A/S
102m
510m
20.8m
Project construction
1969-05-01
5
Two tubes; three lanes each
8.54m
27.4m
Surcharged sandfill replacing existing soil was used to support immersed tunnel. Tension piles
were used to support and hold down open approach and cut-and-cover sections of tunnel
were used to support and hold down open approach and cut-and-cover sections of tunnel
Cast in a casting basin excavated for the purpose, about 10 km
from the tunnel site. Elements were cast in 12.8 m long sections -
first the bottom; then the walls; and, last, the roof. The sections
were separated by a 1.8 m gap into which rebars protruded.
These gaps were filled after concrete shrinkage had taken place
from the tunnel site. Elements were cast in 12.8 m long sections -
first the bottom; then the walls; and, last, the roof. The sections
were separated by a 1.8 m gap into which rebars protruded.
These gaps were filled after concrete shrinkage had taken place
Elements were outfitted at a
pier after floating with
temporary steel foundation
blocks at the free end, two
alignment towers and two sets
of sinking rigs, each consisting
of two 150 ton pontoons
connected by steel girders
pier after floating with
temporary steel foundation
blocks at the free end, two
alignment towers and two sets
of sinking rigs, each consisting
of two 150 ton pontoons
connected by steel girders
Four straddling placement barges were used. Horizontal alignment was accomplished by lines
connected at the top of the element
connected at the top of the element
Gina type. Special gasketted
end closure plates allowed
connection to submerged face
of cast-in-place northern
tunnel. Immersed tunnel is
monolithic, with a contraction
joint between it and the cast-inplace
northern tunnel and a
combined expansion
contraction joint between it and
the north portal building. The
joints are made watertight with
rubber gaskets.
end closure plates allowed
connection to submerged face
of cast-in-place northern
tunnel. Immersed tunnel is
monolithic, with a contraction
joint between it and the cast-inplace
northern tunnel and a
combined expansion
contraction joint between it and
the north portal building. The
joints are made watertight with
rubber gaskets.
The elements are waterproofed with a 2 mm butyl membrane, protected on the bottom by a 9 cm
layer of reinforced concrete and on the top by a 20 cm layer of reinforced concrete, and glued to
the bottom protection and to the walls and roof of the tunnel by a PVC cement slurry.
layer of reinforced concrete and on the top by a 20 cm layer of reinforced concrete, and glued to
the bottom protection and to the walls and roof of the tunnel by a PVC cement slurry.
Sandjetting
No cover provided. 20 cm of reinforced concrete is the only protection to the waterproofing layer.