Zigana: Turkey’s longest tunnel and one of the few tunnels of this length in the world
Overview
Project Summary
2x2 higway tunnel
14.5 km
Cross sectional area: 64.4 m²
Services
Location
Period
Employer/Client
With its 14.5 km length the Zigana Tunnel is the longest tunnel in Turkiye and also ranks amongst the longest tunnels in the world.
It's a double tube highway tunnel (2x2) constructed by New Austrian Tunneling Method (NATM). Cross sectional area of the tunnel is 64.4 m². Maximum and minimum excavation areas are 127 m² and 99 m² respectively.
The new tunnel crosses the mountain at an approximately 560 m lower elevation than the existing tunnel and shortens the distance by 8 km. The existing Zigana tunnel proceeds at an elevation of around 1,800 m.
It enters at an 800 m lower point crossing the Zigana mountains along a 560 m lower elevation.
There are 6 ventilation shafts in the tunnel alignment. As the shafts were tall they were excavated with a Raise Boring Machine rather than by conventional method, thereby saving time.
There are 32 lay-by in the tunnel, 16 in the left tube and 16 in the right tube, 40 vehicle connection tunnels, and 9 transformer rooms connection tunnels.
A total of 2007 m of drilling was performed in the tunnel alignment.
With its 14.5 km length the Zigana Tunnel is the longest tunnel in Turkiye and also ranks amongst the longest tunnels in the world.
It's a double tube highway tunnel (2x2) constructed by New Austrian Tunneling Method (NATM). Cross sectional area of the tunnel is 64.4 m². Maximum and minimum excavation areas are 127 m² and 99 m² respectively.
The new tunnel crosses the mountain at an approximately 560 m lower elevation than the existing tunnel and shortens the distance by 8 km. The existing Zigana tunnel proceeds at an elevation of around 1,800 m.
It enters at an 800 m lower point crossing the Zigana mountains along a 560 m lower elevation.
There are 6 ventilation shafts in the tunnel alignment. As the shafts were tall they were excavated with a Raise Boring Machine rather than by conventional method, thereby saving time.
There are 32 lay-by in the tunnel, 16 in the left tube and 16 in the right tube, 40 vehicle connection tunnels, and 9 transformer rooms connection tunnels.
A total of 2007 m of drilling was performed in the tunnel alignment.