Driving the first of the four rail tunnels from the caisson at Gleisdreieck to Potsdamer Platz Station on Berlin’s north-south rail link started in late November. This follows a more than two-year delay caused by the accidental flooding of the 200m long caisson in July 1997.
The 8.9m dia. Herrenknecht slurry shield was advancing slowly when T&T International went to press, as space restrictions forced the TBM train to be assembled in stages as the machine advanced. It was anticipated that only 15-20m would be driven before late December.
The 580m long southern tunnels pass under the new developments of central Berlin and 7m below the Landwehr Canal. The start of work on this section of the scheme follows the development of a unique strategy for ground support and subsequent launch of the TBM.
Each of the four drives is expected to take three months, with completion by the end of 2001.
