K36 Lammschlucht Gorge, Unter Tänndli Retaining Wall

The Unter-Tänndli retaining structure on the valley side is in poor condition and tilts. It supports the K36 cantonal road (Schüpfheim - Flühli) on the valley side coming up from the gorge. The retaining wall was probably erected in 1956 when the road was widened. An open bored pile wall consisting of reinforced bore piles and top plates was installed to secure the retaining wall on the valley side with respect to the road and the existing em-bankment. The anchoring depth of the bored piles was selected to ensure com-plete anchoring in the deep rock. The bored piles are monolithically connected with the top plates. The crash barrier was mounted onto the guide wall.

Données principales

  • Bored piles d=0.9-1.0 m: 220 m
  • Top plates: 50 m
  • Concrete top plates: 75 m3

Maître d'ouvrage

Lucerne Canton (vif – Transport and Infrastructure Department), Building Section

Ingénieurs du projet

IUB Engineering AG in consortium



Coûts de construction

CHF 440,000


  • Preliminary project
  • Construction project
  • Tendering
  • Implementation project
  • Local site supervision