Belgium, Zeebrugge

Zeebrugge dock

For the new southern quay wall of Albert II dock in the port of Zeebrugge, the THV Fondedile - Franki Foundations realized 10 000 m² diaphragm wall in very densely packed sand layers for which a special heavy grab had to be used.

Technical specifications

Diaphragm wall

10 000 m²
1500 mm thick
36 m deep

Barrettes

479 m²
1500 mm thick
36 m deep

Driven cast-in-place piles

395 no.,
Ø 609 mm
25 m long
2 850 to 3 450 kN safe working load
Inclination piles: 1:5, 1:4 and 1:3

From briefing to design

When Franki Foundations signs the contract in July 2011, the project counts, next to the diaphragm wall, 400 driven cast-in-place piles with a diameter of 508 mm.

But in September, the briefing changes. The loads applied to the piles are adapted, and so must be the diameter which becomes a 609 mm. At that moment, we have no machine capable to realize this, but that does not stop us. We take our Hitachi CX900 and we transform it in-house in order to meet the requirements. And so it does.

Technic and timing

It has been quite a challenge to adapt the project in the given timing. Our Engineering department had to re-design the project, our repair and maintenance service had to modify the machine, and even the team had to adapt itself to a new working method. Indeed, the machine had only driven precast piles in the past, and it was now asked to drive in the pile, concrete it and withdraw the steel tube. Which implied reinforcing the mast among other changes on the rig.

With joint efforts of BESIX and Franki Foundations, it all turned out right, and we were able to drive in up to 5 piles a day in the port of Zeebrugge.