S21 – Foundation

Ingenhoven Architekten, Düsseldorf/Germany

Planning time
2011 − 2020

Construction time
2014 − 2025

Services by Werner Sobek
Structural engineering (WP 3 − 5 + 8)

50,000 m²

DB Projektbau GmbH, Stuttgart/Germany

Bahnprojekt Stuttgart-Ulm e.V., Stuttgart/Deutschland (images)
Ingenhoven Architekten, Düsseldorf/Deutschland
Peter Wels, Hamburg/Deutschland

The rail project between Stuttgart and Ulm requires multiple modifications to the built environment of Stuttgart, a regional capital. One of these modifications is a through station with 8 platforms. This new underground station consists of a grand hall of approximately 420 by 80 m. It is based on a ‘concrete trough’ construction that merges seamlessly into a ‘shell roof’ of white concrete.

The entire construction is of seamless and solid design, the only joints can be found in the transition areas at the northern and southern ends of the building. The ‘concrete trough’ is made of waterproof concrete and therefore the technical requirements for the solid construction are considerable. It consists of lateral walls and a slab of varying thickness, ranging from 1 to 2.5 m below the platforms and the track beds respectively.

The trough sits entirely on piles, except for the bridge construction above an existing underground tunnel. The ram piles usually end well above a layer of gypsum which in turn constitutes a natural barrier towards the subjacent water table.