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Reference list (excerpt)

Complete design and consulting services from the outline design and detailed design to the preparation of tender documents, as well as construction design for the M+E facilities.

The motorway BAB A71 from Erfurt to Schweinfurt crosses the Thuringian Forest by means of the Rennsteig tunnel, Germany's longest motorway tunnel. From both portals towards the centre, the tunnel has an inclination of 1.65 and 2.00 %. The tunnel with a standard cross-section of type 26 (according to BMV ARS 16/85) cuts across quartz porphyry, breccia, tuff, conglomerate, sandstone, clay and siltstone, as well as soil creep debris in areas with shallow cover. The caverns of the ventilation are placed in the cross valleys. The ventilation caverns are used for intermediate access to the tunnel advance. The necessary adits are used for the intake of fresh air, shafts with a diameter of 6.2 m are constructed for the exit air. The longitudinal ventilation of the tunnel sections is supported by means of fans with a diameter of 1,450 mm. Depending on its quality, the excavation material is used as concrete aggregate or anti-freezing material, or in dams and waste sites.