Berlin

Museum of Modern Art "berlin modern"

Turnkey construction pit for the new building at Berlin’s Kulturforum

Construction pit under Berlin’s groundwater conditions

The subsoil at the site consisted of sandy fill containing construction waste and solid structural elements, upper valley sands and gravels, glacial marl, as well as lower valley sands and gravels. At the same time, subsoil conditions in Berlin are characterised by high groundwater levels and well-drained soils. A watertight trough-shaped excavation was therefore constructed for the new building. The construction pit walls were constructed as diaphragm walls to depths of around 25 m and secured with approximately 500 grouted anchors.

Diaphragm walls and steel pipe stiffeners for excavation stabilisation

In areas where it was not possible to install grouted anchors, the construction pit was stabilised using internal steel pipe bracing. A total of around 200 t of steel was used for this purpose. The steel pipes employed reached lengths of up to 42 m with a diameter of 1 m and were adapted to the geometric and structural requirements of the construction pit.

DSV sealing slabs for sealing and buoyancy control

The lower boundary of the construction pit was formed by a DSV sealing slab covering an area of approximately 8,000 m², which was constructed using the jet grouting method. To prevent buoyancy, the sealing slab was back-anchored with around 1,000 micro-grouted piles. The piles provide buoyancy control both for the sealing slabs and, subsequently, for the building itself. Due to the ground conditions, drilling depths of up to 40 m were required for individual grouted piles. The DSV sealing slabs were constructed in accordance with the local ground conditions and adapted to the requirements of the structure.

Inner-city special civil engineering at the Kulturforum

The project was carried out in the inner-city setting of Berlin’s Kulturforum. The construction of the diaphragm walls enabled the construction pits to be constructed within the constraints of a densely built-up environment. The shoring, waterproofing and foundation elements were coordinated to facilitate the construction pits. The combination of diaphragm walls, grouted anchors, steel pipe stiffeners, DSV sealing slabs and micro-grouted piles formed the basis for the subsequent building construction work.

The foundation for the new Museum of Modern Art

By excavating the construction pit, PORR special civil engineering laid the groundwork for the construction of the Museum of Modern Art ‘berlin modern’ at the Kulturforum. The trough-shaped construction pit, the DSV sealing slabs as well as the extensive shoring and stabilisation measures form the foundation for the construction of the museum building.