Technical specifications

Scope of works:

• Foot and cycle path tunnel, length 114.77 m, max. clear width 6.45 m, clear height approx. 4.22 m.
• Tunnel structure with double lining, driven using the drill and blast method with reinforced/unreinforced sprayed concrete lining and anchors protecting against caving in and deformation.
• Umbrella waterproofing with plastic sheeting and a sidewall drainage system.
• The concrete inner lining is reinforced in the portal areas, with steel fibres within the standard area of the mined tunnel.
• The carriageway will be constructed on the open rock floor.
• The north portal block is to be aligned to the slope.
• The south portal will be redesigned with its ascent to the Georgsberg mountain.

Special feature:

• State-of-the-art technology is used for blasting, as the buildings extend to a minimum distance of 8m from the excavation soffit and some of them are listed as historic buildings.

Construction method

• Drill and blast

Geology

• slaty pearl gneiss