On Santa Barbara's Day 2015 we celebrated the breakthrough of Falkenberg Tunnel under the Umfahrung Schwarzkopftunnel Project in Spessart mountain in Germany. After almost two years of excavation works, the final meters of the last tube were completed a few days before the ceremony.
The figures are quite impressive: we constructed 5 tunnel tubes with total length of 6.235 m. Falkenberg Tunnel is the longest with 2.420 m long right tube and 2.380 m long left one but the tubes of Metzberg (right tube - 555 m, left tube - 530 m) and Hirschberg (350 m) tunnels were nonetheless challenging for us. We excavated 557.000 m3 of earth and rock mass, we executed reinforcement structures using 112.000 m steel arches and 120.000 m3 spraying concrete.
Our experts worked at 4 tunnel profiles simultaneously. The scope of our works included excavation with NATM using blasting with division of the profile into top-heading, invert and bench, followed by supporting works. Our blasters used 400 t of explosives to get through the rock. The difficulties were challenging throughout the whole construction process: unstable geology, partial high water influx, highly demanding conditions for the personnel, machinery and equipment. Nevertheless, with the help of our experienced and skilled workers and experts, we finished the works and met all the requirements and schedule of the client.
