Niayesh Tunnel
The Niayesh Tunnel Project is in the north of Tehran, Iran.
Unlike the Tohid and Resalat Tunnels, this tunnel has two parallel roads that are within 130 m (430 ft) of each other for most of the route. Traffic in the north tunnel flows from east to west. In the south tunnel it flows from west to east. For the first time in Iran, there are some embranchments of other tunnels among main tunnels. Among the north tunnel, Kordestan tunnel with a length of 950 m (3,120 ft) – the same length as the Resalat tunnel – is branched from the north tunnel that it makes accessible to downtown and Hemmat highway through a connection between the north tunnel and Kordestan Highway. Also, the north Kordestan highway would be connected to the south tunnel through a 194-metre (636 ft) tunnel that provides traffic flow to east Tehran. The total length of the main tunnels as the second longest urban tunnel in the world excluding ramps is 6,658 metres (21,844 ft). The total length of the main tunnels and access tunnels, including ramps, is 10,252 metres (33,635 ft).
Main tunnel execution started 26 March 2011 after finishing the site mobilization. On 19 March 2012 all the excavation finished. The average rate of excavation in tunnel was 18.5 metres (61 ft) per day with NATM method of excavating. It was one of the fastest excavations in the world, considering the tunnel dimensions. In this project 200,000 m3 (7,100,000 cu ft) soil excavated in the ramps areas.
The concrete volume poured was 270,000 cubic metres (9,500,000 cu ft), of which 95 percent was done during 7 months using 17 formworks. The average rate of pouring concrete was 30 metres (98 ft) per day for the tunnel's full face. This project has 8,000-square-metre (86,000 sq ft) peripheral buildings which are built within three months. The 4,000-square-metre (43,000 sq ft) main control building was built by modern methods and prepared for ITS systems installation within two months. In executing parts of the project, considering the job difficulties, there were three working shifts each day that the number of labor achieved to 4800 persons and it can be considered 6000 persons including indirect workers.
The project's Attributes during exploitation
...
Wikipedia