Erstellung einer Baugrube unter dem Amsterdamer Hauptbahnhof mithilfe der Bodengefriertechnik.

Execution of a building pit under Amsterdam Central Station using ground‐freezing technology Construction of a building pit underneath one of the busiest railway stations in the Netherlands, with as a little disturbance to the public as possible, calls for innovative engineering solutions. This paper focuses on the design and execution methods for the project "Cuyperstrap", a staircase connecting the entrance hall of the Amsterdam Centraal Station and the subjacent metro distribution level. Due to the challenging boundary conditions, e.g. limited workspace, high groundwater level and fragile adjacent structures, common methods for constructing building pits were not applicable. Using a retaining wall consisting of artificially frozen ground Max Bögl BV was able to execute the project successfully. Artificial ground freezing is a technique commonly known in tunnelling and mining projects, but as is shown here can also be applied to other fields of structural engineering. Freezing the pore water in the ground increases the bearing strength and makes the frozen area impermeable. The iteratively refined design included structural and thermal calculations, taking into account the on‐site conditions. Starting with drilling of the freeze pipes and installation of the site equipment the construction period commenced at the beginning of 2019. The freezing period started in April and ended in November, after completion of the outer concrete structure. The Cuyperstrap was be opened to the public in July 2020. [ABSTRACT FROM AUTHOR]