Retaining wall for the Poľana tunnel precuts

The two tunnel portals were stabilised with supporting structures made of gabions (cages filled with rocks). For the sections of slope on the sides, gabion gravity retaining walls were used, while the front sides were built as geosynthetic-reinforced supporting structures with gabions on the face. Four-metre-long uniaxial geogrids made of polyester were used for reinforcement. A tie-back anchored retaining wall was built to stabilise the embankment of the cut formed in front of the eastern portal of the Poľana tunnel. It was completed in stages, during which tie-back anchored elements with prestressed strand anchors and reinforced concrete ribs were produced. Cladding made of gabions was used for the infill.