The 176-metre-high Estrel Tower stands on Sonnenallee in Berlin-Neukölln and, as Germany’s tallest hotel, has a significant impact not only on Berlin’s skyline.
As part of the extensive ground investigations, boreholes were drilled to a depth of 60 metres. Beneath the well known Berlin sand and glacial till layers, the team encountered a rarely documented geological layer from the Holstein Warm Period. These complex subsoil conditions required a particularly careful settlement analysis and foundation planning.
Following an intensive evaluation of options, CDM Smith opted for a combined pile-slab foundation (KPP), an uncommon but technically optimal solution under Berlin’s ground conditions. The concept comprised:
- 52 large-diameter bored piles (approx. 20 m long, 1.80 m in diameter)
- A 3.60-metre-thick base slab
The analyses were carried out using an integrated structural model in combination with a geotechnical model (G-model) developed by CDM Smith.
Once completed, the Estrel Tower will combine office space, hotel facilities, and modern apartments, creating a new urban focal point in Berlin-Neukölln.
Through its ground investigation and foundation design work, CDM Smith has made a significant contribution to the safe and sustainable construction of the Estrel Tower. The project exemplifies engineering excellence, innovative planning and the successful management of complex geotechnical challenges.