CHENNAI: Chennai Metro Rail Limited (CMRL) started tunnel work on the stretch between Greenways Road and Adyar in corridor-3 under the second phase on Thursday. The 1.2 km stretch between Greenways Road and Adyar is part of the 45.8 km Madhavaram to Sipcot corridor. This particular stretch is part of Kellys to Taramani contract TU02, which has been awarded to Larsen and Toubro.
The underground tunnel package is to be constructed in approximately 52 months by using eight tunnel boring machines working simultaneously in various stretches. The Herrenknecht TBM that is tunnelling has been rechristened Kaveri after river Kaveri. The next TBM from Greenways Road is named Adyar. The Kaveri TBM is scheduled to arrive at Adyar Junction in August.
This TBM will tunnel through DB Road, crossing the Adyar river near Thiru Vi Ka Bridge, and eventually arriving at Adyar Junction station. The tender to construct 12 km twin bored tunnels from Kellys to Taramani Road Junction also involves the construction of diaphragm walls of station box and entry and exit structures of Chetpet Metro, Royapettah GH, Thiruvanmiyur Metro stations and part diaphragm wall of Greenways Road Metro.
A total of 23 TBMs will be used to build the extensive network of underground tunnels of Phase 2, which includes new TBMs imported for the works and TBMs remanufactured in India. These TBMs will be launched and retrieved multiple times till completion from the shafts at various locations, according to a Chennai Metro spokesperson.