Unconventional suspensions/supports of metro station Amsterdam Central

The element for the North South Metro line underneath Amsterdam Central Station was temporary supported with a suspension structure connected to the roof during immersion. This kept the element ‘hanging’ on a fixed location during the sandflow for the final tunnel foundation.

suspensions CS 0
CS - suspension on deck
suspensions CS 2
suspensions CS 1
suspensions CS 3
suspensions CS 4
CS immersion 3D 4
 

The main reason we designed these supports was because of the floor construction underneath the metro station element. By using conventional methods, the pressures occurring in this phase could damage the underwater concrete floor underneath the element.

The supports existed of 4 hydraulic steel struts which where fixed on the deck of the tunnel element. The supports where be connected from the roof of the element to the reinforced base slab above the element which is the central passenger passage of the train station. These supports could be adjusted in height and could deal axial rotation, by the use of hydraulic jacks integrated in the system. These hydraulic jacks are also used to measure the vertical loads during  the sandflow.