Introduction : Extruded Concrete Lining Method


  1. Construction of high-quality linings
    Denser concrete with greater strength enables the construction of high-quality concrete linings.
  2. Linings with a broad range of applications
    This method enables rational construction of concrete linings according to the site condition such as reinforced concrete, nonreinforced concrete, fiber-reinforced concrete, steel-reinforced concrete and prestressed concrete linings.
  3. Superiority of working conditions in tunnel
    This method can be applied to mountainous tunneling, and as working conditions in the tunnel is superior compared to the conventional tunneling method, cost for ventilation facilities can be minimized.
  4. Minimization of ground settlement
  5. Saving of construction time and cost
    The type of lining can be selected according to the geological condition, and secondary lining can be eliminated depending on the use of the tunnel. Construction cost therefore can be reduced and construction period can be shortened.

Mechanism of tunnel driving

Construction flows by lining reinforcement method

  1. When reinforced concrete is used
    (cyclic concrete placement)
  2. When nonreinforced concrete is used
    (continuous concrete placement)

Applications to actual tunneling

Construction of the second Shinano-gawa water tunnel
Diameter : 8.40 m
Construction length: 3,100 m
Major soil type:Sandstone and
Depth of tunnel:2.0m to 80.0m

Konan shield tunneling
Diameter: 6.60 m
Construction length: 1,860 m
Major soil type:Diluvial gravel
Use:Utility conduit
Depth of tunnel:11.4m to 17.0m

Construction of the east side of the Akima Tunnel on the Hokuriku Shinkansen railway line
Cross section: 10.70 m wide
and 9.92 m high
Construction length: 3,805 m
Major soil type:Tuff
Depth of tunnel:Maximum 220.0m

Main civil engineering work as part of the construction of new Hidaka power plant
Diameter: 3.99 m
Construction length: 6,082 m
Major soil type:Lava and
Depth of tunnel:Maximum 190.0m