15 November 2022
Last week, the first 2 foundation tiles were placed on the bottom of the Scheur in the Port of Rotterdam. The foundation tiles form the temporary foundation for the Maasdeltatunnel, part of the A24 Blankenburg connection. Strukton Immersion Projects (SImP) is placing the foundation tiles on behalf of BAAK (a consortium of Ballast Nedam, DEME Group and Macquire).
As many as 12 foundation tiles will be installed for the two tunnel elements, which will be immersed in spring 2023. The foundation tiles weigh about 95 tonnes each and 4 foundation tiles have a size of 7 x 7 metres and 8 foundation tiles have a size of 6 x 6 metres. For placing the concrete foundation tiles, DEME and W. Smit BV, among others, are cooperating. After the foundation tiles are placed, divers will disconnect the lifting equipment at a depth of about 30 metres and then prepare to place the next foundation tile.
Tides and currents at this location make placing the foundation tiles extra challenging, but still manage to place the foundation tiles on the bottom within a few centimetres tolerance. GEOCON is used to determine the position of the tile. For this purpose, the system is duplicated. Both GPS and measuring prisms are used to determine the location and orientation.
SImP has extensive experience in placing the foundation tiles on the ground. Foundation tiles were previously placed by Strukton for the Limerick Tunnel and the North/South Line IJ Tunnel, for example. The gigantic concrete foundation tiles are laid with the accuracy of a few centimetres.
There is no subtitute for experience
Placing the foundation tiles on the bottom is one of many preparations for sinking the two tunnel elements of the Maasdeltatunnel. The two tunnel elements will be immersed in spring 2023. The Blankenburg connection will make it possible to drive from the A20 near Vlaardingen directly to the A15 in the Botlek.
Peter van Westendorp
Directeur Strukton Immersion Projects