BREAKTHROUGH AT THE GOTTHARD.

November 2nd, 2006. The JV TAT (Implenia AG, HOCHTIEF AG, Alpine Mayderer Bau GmbH, CSC Impresa Costruzioni SA and Impreglio S.p.A.) deploys two identical Gripper TBMs manufactured by Herrenknecht AG on behalf of the client Alptransit AG: the S-210 "Sissy" and the identical S-211 "Heidi" (each 8.830m in diameter) have been drilling their way throug Alpine rock since November 2002 and February 2003. After 3 years and 10 months, the S-210 TBM  achieved breakthrough in the eastern tube at the multi-purpose station “Faido“ on September 6th this year. On October 26th, the S-211 did the same and pulled alongside of the S-210, reaching breakthrough level and its stage finish, after almost 15km of tunnelling under the most difficult geological conditions. Like the S-210, the S-211 reached its stage finish with maximum precision.

When the two southbound Herrenknecht Gripper TBMs S-229 and S-230 (each 9.580m in diameter of the JV AGN (Murer AG and STRABAG AG) reach the end of their heading and their final stage, on the tunnel section “Amsteg“, in June and October 2006,  the excavation works at the Gotthard are scheduled to be interrupted until mid-2007. This interruption is required for a comprehensive modification of the S-210 and S-211 TBMs in the tunnel. The TBMs will be completely disassembled and all diameter-related parts be enlarged by 60cm. After the modification, both tunnel boring machines are scheduled to bore another 12 kilometers through the mountain along the last long tunnel section between Faido and Sedrun.