Tube combined walls

The tube combined wall is a combined system with:

• steel pipes as primary elements
• double AZ sections or U sections as intermediate piles.

A lot of combinations are possible because of a systematic variety of pipes and intermediate piles.

ArcelorMittal Projects produces combined piles by making the tubes at the right length and providing them with interlocks. All necessary welding can be done by our own team.

The possibility to use different combinations in combined walls allows them to take loads that cannot be taken by conventional sheet piles. Obtaining an elastic section modulus of more than 10 000 cm³/m is no problem.

To calculate the section modulus or weight of combined walls you can use this calculation sheet.

AZ sections are ideal intermediate sheet piles in combined walls for the following reasons:

• Load-displacement behaviour is far better than that of double and triple U-piles, so settlements are less.
• High soil and water pressures are increasingly transferred to the pipe as normal tensile stresses (membrane effect).
• Because of their geometry, AZ intermediate sheet piles are coping better with driving deviations of the pipes than U-piles, because of the triple hinge system.
• Larssen-type interlocks contribute to the high performance of AZ intermediate sheet piles.
• In tests is measured that AZ intermediate sheet piles can resist very high ultimate loads, for example up to 57 m hydraulic head for an AZ 18 (S 430 GP).

For more information about this, see our brochure AZ sheet piles in combined walls.