Tehran Subway Line4
- Client: Tehran Metro CO
- Project location: Tehran,Iran
- Design start date: 2009 Dec
- Construction start date: 2015 Dec
Project status up to now:
Line 4 of Tehran subway is one of the 9 lines which was in construction priority. Since the main purpose of this line is transferring passengers from city to Mehrabad Airport, this line must pass through three main strategic points, Bimeh St., Mehrabad airport passengers’ terminal 1 & 2 and Mehrabad airport passengers’ terminal 4 & 6. Line 4 is 22 km long with 19 passengers’ terminal and a special route includind three terminal forMehrabad airport. Bolandpayeh’s contract engineering services in line 4 of Tehran subway was started in 2009 by TTBP. Project scope of works is 2 km of tunnels, 12 km tracklaying, 4 underground passengers’ terminal, 2 T junctions, 2 ventilators and 2 train’s lubritorium. New Austrian Tunneling Method (NATM) for metro tunnel and pile and rib network of primary structure for under for underground terminal such as line 3 was chosen for this subway line as well. In order to solve NATM disadvantage, TTBP develop a resource paln, which helps Bolandpayeh using form works in series and parallel patterns and utilized special mix design. As a result Bolandpayeh successfully achieved average advancement rate of 30 meters of tunneling (including excavation and temporary and permanents structures) per day and 80 m per day for track laying which are beyond what other companies have achieved in Iran. In addition the construction duration of underground stations successfully reduced up to 30%, using construction of platform wceiling slab at ticket hall floor slab elevation and then excavation of the passenger platform. Section 1, from Ferdowsi Square to Darvazeh Shemiran, on April 2008, Section 2 from Darvazeh shemiran to Shohada Square on Feb. 2009, Section 3 from Ferdowsi Square to Engelab Square on May 2009, opened to public. On Feb. 2016 Mehrabad airport route was constructed by Bolandpayeh and opened to pulbic. An extension of line 4 is currently under preliminary studies by TTBP. This extension includes 2.5 km of tunneling and 1 connecting terminal, which connects line 4 to line 8.