The Ljubno tunnel - Right tube

DARS d.d., Ulica XIV. divizije 4, 3000 Celje, Tel. +3863 544 20 00

INR 40,64 Crore

PRELIMINARY DESIGN, APPROVAL DESIGN, TENDER DESIGN, FINAL DESIGN

2010

Basic information:
• Total length of tunnel: 260 m
• Area of excavation profile: 141.30 m2
• Maximal overburden height: 25 – 30m
• Longitudinal gradient: constant 1.14 %

The existing right tube tunnel Ljubno, which has been in use for approximately 40 years was in the context of the design of the highway program scheduled for reconstruction as part of a motorway section Peracica-Podtabor. Between the axial distance of the old right and new left tube is 42 m. The expansion of an existing profile to a two lane tube with an emergency lane as part of the reconstruction process was planned according to principles of  NATM. As with the left tube, the main feature is in the planning of the construction of the tunnel tubes derived from specific chemical-physical properties of »sivica« such as swelling and causing sulphate corrosion of concrete. The thickness of the planned primary lining amounted to 30 cm, extending the profile was divided into the top and the bench + the invert. The reconstruction of such kind is the first in Slovenia. As with the left pipe the outdoor feature arrangements of the tunnel will be made with reinforced earth, which will, together with the left tube and the surrounding area, adjust into an architectural whole.