Toheed Tunnel is located under Chamran- Navab Highway between Fatemi St. north of Toheed Sq. and south of Azarbaijan intersection.The length of tunnel is 2,136 m each side with an overall 867 m length of ramps and a total cross section of about 300 m2.
The effective width of each portal is 12.5 m with three traffic lanes on each side and a pedestrian walkway for maintenance personnel. These twin tunnels are separated by a series of pillars with diameters of 1.5 m placed at 4 m intervals.
The circulation of filtered air is passed and monitored by a central control which is a five floor building.
The highest point in the Tunnel is 8.5m above the ground and effective traffic width is 11 m. Overburden thickness over the tunnel varies from 6 m at the entrance portals to 23 m at the point directly under Metro Station No.2 at the Azarbaijan Street intersection. This Project was completed in 30 months. Precast concrete waffles are used for interior finishing.
Location: Tehran, Iran
Length 2,136 m (each side)
Cross section area: 300 m2
Number of lanes: 3 each side + 1 emergency lane