Innerstädtischer Tunnelbau - Herausforderungen des Spezialtiefbaus am Beispiel der S-Bahnlinie S21 in Berlin

Tunnelling in urban area - Challenging demands on the geotechnical construction using the example of the S21 railway project in Berlin.

The S21 railway project is one of the most important infrastructural projects in Berlin. With existing structures above and below ground plus further urban developments in the pipeline, the result is highly diverse boundary conditions for the numerous excavations needed for this project. In particular, the proximity to underground structures for long-distance and metro lines as well as the B96 trunk road and Invalidenstrasse, which have to remain open during construction, place high demands on the engineering. This report describes the ensuing shoring and waterproofing systems for the excavations and, in particular, the challenges posed by tunnels beneath buildings, including the high-rise building MK8. The various technical and procedural requirements of a complex urban tunnelling project are presented from the perspective of the checking engineers appointed by Germany's Federal Railway Authority.