Protection contre les glissements de terrain et les laves torrentielles MILIBACH TORRENT, HASLIBERG, CANTON OF BERN, CH

Transcription

1 Protection contre les glissements de terrain et les laves torrentielles MILIBACH TORRENT, HASLIBERG, CANTON OF BERN, CH

2 MILIBACH TORRENT, HASLIBERG, CANTON OF BERN Protection contre les glissements de terrain et les laves torrentielles Projet Milibach Torrent, Hasliberg, Canton of Bern Rue Oberstafel Code postal 6086 Ville Hasliberg Reuti Pays / région Suisse Année d installation 2011 Client. Situation In August 2005, a storm in the Weiler Reuti and in Meiringen had caused serious debris coverage and severe damage. To protect the two settlements, a cascade comprised of 13 flexible debris flow barriers was installed to retain a cumulative volume of up to 10,000 m³ was installed. On October 10, 2011, heavy rainfall triggered a shallow landslide containing a total of 2,000 m³ of schist in the drainage area of the Milibach river. Approximately 80 mm of rain had fallen onto a 70 cm layer of existing snow in 12 hours. The Swiss Federal Office for Environment (FOEN) categorized these heavy rainfalls as the 100-year event. Description This multilevel debris flow barrier system successfully retained an estimate 2,000 m³ of debris from the October year event before the slide had any opportunity to gain momentum and cause significant damage, as had happened in The event filled barrier no. 2 completely and barrier no. 5 partially. Barrier 1, which was situated above where the shallow landslide was triggered, remained unaffected, while barriers 3 and 4 were not filled as they have a higher basal opening. Stopping the 2,000 m³ of debris helped prevent further erosion along the unstable banks of the Milibach River and dissipated an event that could have caused damage to the settlements further downstream. After an in-depth investigation during an on-site inspection, the customer decided to leave barrier no. 2 filled to protect the riverbanks. The debris held by barrier no. 5 is also being left and should be carried away over time as the water drains naturally. Systèmes Autres applications installées Multi hazard barrier Protection contre les glissements de terrain et les laves torrentielles Protection anticorrosion GEOBRUGG SUPERCOATING Hauteur du système 7.0 m Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 2/9

3 Longueur du système 500 m - 7 m Nombre de barrières 13 Capacité de rétention m³ Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 3/9

4 Filled barrier after the impact - view from downstream Satellite image of the storm that moved across the northern Swiss Alps on October 10 (source: SF Meteo website) Filled barrier after the impact Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 4/9

5 Filled barrier after the impact Partially engaged UX-barrier - ready for more Event mapping Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 5/9

6 Erosion and slope instability Staking Drilling with a specially equipped excavator Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 6/9

7 Installing flexheads Foundation with installed flexheads Ring net ready to be placed Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 7/9

8 Connecting the ring net to the ropes Final assembly of the components Anchor test Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 8/9

9 Pour toute question, contactez votre spécialiste Geobrugg le plus proche Alexander Bittendorfer Project Manager Germany South Téléphone Mobile Geobrugg AG Aachstrasse Romanshorn Suisse A company of the BRUGG Group Certified to ISO 9001 Protection contre les glissements de terrain et les laves torrentielles Milibach Torrent, Hasliberg, Canton of Bern, CH 9/9