Tunnel References
Project documentation: Project for obtaining a building permit, project for tender, project for implementation, project for operation and maintenance
Investor: DARS, Družba za avtoceste v Republiki Sloveniji d.d.
Object properties: The tunnel is two-tubed and two-laned, length L=360 m
The highway section A5 Maribor – Hungarian border (Sp. Senarska – Cogetinci) includes the two-tubed tunnel Cenkova. The special feature of the tunnel is its small cross section width, which dictated the construction of tunnel tubes with the execution of an intermediate tube. The tunnel was entirely executed through mechanical excavation using a tunnel excavator and according to the principles of NATM. We performed all project phases for the client.
Project documentation: Project for obtaining a building permit, project for tender, project for implementation, project of works performed, project for operation and maintenance
Investor: DARS d.d.
Client: DARS d.d.
Object properties: The tunnel is two-laned with a hard shoulder, length L=260 m
The left tube of the Ljubno tunnel at the highway section Peračica – Podtabor was built in 2007. The cross section width between the existing right and the new left tunnel tube is 42 m. The construction of the tunnel was planned according to the NATM principle. The main characteristics in planning the construction of the tunnel tube were the specific chemical-physical properties of the pyrite-clay (hill layers) such as swelling and the content of pyrite, which represents a hazard for the sulphate corrosion of concrete. The thickness of the planned primary coating was 30 cm, the excavation of the profile was separately divided into a skullcap and joined step and floor arch. The left tunnel tube represents a rarity in tunnel construction outside of urban areas, because the secondary coating with a thickness of 35 cm is reinforced due to possible changes in the rheological properties of surrounding hills. The tunnel is also special due to the execution of the external tunnel arrangement with reinforced earth, which, together with the wider surroundings, represents a unified architectural whole.
Project documentation: Design concept, project for obtaining a building permit, project for tender, project for implementation
Investor: DARS d.d.
Client: DARS d.d.
Object properties: The tunnel is two-laned with a hard shoulder, length L=260 m
The existing right tube of the tunnel Ljubno that has been used for approx. 40 years was foreseen within the design of the highway program for reconstruction as a part of the highway section Peračica - Podtabor. The cross section width between the existing right and the new left tunnel tube is 42 m. The execution of the reconstruction with the expansion of the existing profile to a two-laned profile with a hard shoulder was designed according to the NATM principle. Like the left tunnel tube, the main characteristics in planning the construction of the tunnel tube were derived from the specific chemical-physical properties of the pyrite-clay (hill layers) such as swelling and the content of pyrite, which can cause sulphate corrosion of concrete. The thickness of the planned primary coating was 30 cm; the expansion of the profile was separately divided into a skullcap and joined step and floor arch. Such reconstruction is the first in Slovenia. Like for the left tube, the external arrangement of the tunnel shall be performed with reinforced earth, which will, together with the left tube and the surrounding hills, represent a unified architectural whole
