menu
PRODUCTS

Coastal structures

Hybrid caissons and L-shaped caissons (for quay walls)

Concrete caissons have been used for a wide variety of large-size gravity type structures, including breakwaters, quay walls, and revetments, and generally consist of reinforced concrete members. Hybrid caissons, on the other hand, use composite members of steel and concrete as components. Thanks to the mutual characteristics of high-strength steel and durable concrete, hybrid caissons offer distinguished durability and are also characterized by their light weight, high ductility, and relative ease of application to long, large, and special-shaped quay walls.
Hybrid L-shaped caissons (blocks) are based on hybrid caissons and have an L-shaped structure. Outfitted with a composite slab on the front wall and a steel strut on the rear face, hybrid L-shaped caissons have a high degree of strength.
Experiments and analyses prove that hybrid L-shaped caissons have  equivalent earthquake-resistance to other gravity type structures, including caissons, and they have been adopted for structures constructed in very deep water. In addition, hybrid L-shaped caissons are low in unit weight and consequently can be extended longer than conventional L-shaped blocks.

Construction examples

Name of construction work
-11 m quay wall caisson construction work in Gamagori Zone of Mikawa Port
Client
Aichi Prefecture
Purpose/Function
Quay wall (-11 m)
Year completed
2011
Dimensions (m)
50 (length) × 9.2/14.7 (width: upper/loader) × 13.5 (height)
Quantity (/case)
Dead weight = 3878 tons (steel weight = 303 tons, Con. = 1145 m3)
Design overview
Installation water depth: -11.5 m, design seismic coefficient: 0.17
Features
Case length: 50 m, manufactured in marine dock

▲Steel shell before concrete application

Name of construction work
Shin-okitsu quay wall in Shimizu Port
Client
Ministry of Land, Infrastructure, Transport and Tourism Chubu Regional Development Bureau
Purpose/Function
High earthquake-resistance quay wall
Year completed
2009
Dimensions (m)
Height = 18.5, width (upper/lower) = 11.5/22, length = 24.6 m
Quantity (/case)
Dead weight = 2516 tons (steel = 305 tons)
Design overview
Installation water depth: -16 m, design seismic coefficient Kh = 0.25
Features
Overhanging footing length = 4.5 m on ocean side, 6.0 m on land side
Name of construction work
L-shaped block manufacturing work for quay wall construction in Central Japan International Airport
Client
Enterprise Bureau, Aichi Prefecture
Purpose/Function
Quay wall (lighter’s wharf)
Year completed
2000
Dimensions (m)
Height = 8.6, width (upper/lower) =0.8/10.0, length =40.0 m
Quantity (/case)
Dead weight = 891 tons, steel = 75 tons, Con. = 304 m3
Design overview
Installation water depth: -6.1 m, design seismic coefficient Kh = 0.18
Features
Overhanging footing length = 2.0 m on ocean side, 8.0 m on land side
Remarks
Foaming urethane for impact relaxation sprayed at the time of back filling
Name of construction work
Port repair work in Kanegasaki Zone of Tsuruga Port
Client
Tsuruga office of Port, Reinan Promotion Branch Office, Fukui Prefecture
Purpose/Function
Quay wall (-7.5 m)
Year completed
1999
Dimensions (m)
Height = 9.0, width (upper/lower) = 6.0/21.0, length = 30.0 m
Quantity (/case)
Dead weight = 973 tons (steel = 122 tons, Con. = 348 m3)
Design overview
Installation water depth: -8 m, design seismic coefficient Kh = 0.20
Features
Overhanging footing length = 3.0 m on ocean side, 12.0 m on land side
Remarks
Buttress added for footing overhanging on land side
Name of construction work
Kitakyushu Port (Hibikinada Zone) Quay wall Caisson
Client
Ministry of Transport (current Ministry of Land, Infrastructure, Transport and Tourism) Fourth District Port Construction Bureau
Purpose/Function
Quay wall (-15 m)
Year completed
1998
Dimension (m)
Height = 17.1, width (upper/lower) = 4.0/10.8, length = 35.0 m
Quantity (/case)
Dead weight = 1670 tons (steel = 170 tons, Con. = 612 m3)
Design overview
Installation water depth: -15.6 m, design seismic coefficient Kh = 0.10
Features
Overhanging footing length = 2.8 m on ocean side, 4.0 m on land side