Munich's second core S-Bahn route - special geotechnical investigations for a challenging inner-city project

摘要

The new urban railway tunnel, Munich's second core S-Bahn route, is a project with challenging geotechnical issues. Particularly the construction of the Hauptbahnhof and Marienhof stations with their 40 m deep excavation pits and platform tunnels with a cross section of 340 m(2) will exceed the limits of previous experiences in Munich. Building measurements like this lead to extraordinary issues. For Munich's second core S-Bahn route special investigations were carried out to clarify these upcoming questions. This paper describes the special investigations associated with the planned slurry shield tunnelling. Investigations to evaluate the abrasiveness of loose soils, the slaking of fine-grained soils and the emerging effort for separation are presented. In addition, the course of action to determine the settlements due to tunnelling will be explained as well as the procedure of lifting the tunnel tubes of an existing underground line by the means of compensation grouting.