Chennai: Tunnel boring machines (TBMs) will begin burrowing beneath Washermenpet and May Day Park in the last week of September or October first week to build the underground infrastructure for metro rail, according to a Chennai Metro Rail spokesperson. The spokesperson told City Express that the tunnel boring machines are being lowered into the vertical shafts in these two sites and operations are set to begin soon.
Metro rail is using 11 TBMs, each costing Rs 60 crore, assembled at specific sites to drill 24 km with 19 stations beneath the city to create infrastructure for its two corridors. The spokesperson said that the parts of the tunnel boring machines are also being lowered at Shenoy Nagar. However, in Saidapet, tunneling operations will start only when the TBMs arrive from China.
Meanwhile, tunneling operations between the 939 - metre stretch between Nehru Park and Chennai Egmore is on in full swing and till now Metro Rail has tunneled 72 metres and installed 60 tunnel rings. The work is expected to be finished within five months. But the biggest challenge for Metro Rail will be to dig nine metres below the densely-populated Washermenpet-Manali stretch. “We have six instruments, including crack meter and optical meter to monitor the tunneling operations,” the spokesperson said.
Boring machines are being lowered into the vertical shafts in these two sites and operations are set to begin soon.
Currently, the diaphragm wall construction is fully completed in Washermenpet, May Day Park, Nehru Park and Shenoy Nagar. On the elevated stretch, the plinth concreting for track laying has been carried out for a length of 2,500 metres. He also said that 1.25 km of track is ready for fastening between Vadapalani and CMBT stations.
Meanwhile, Chennai will have the opportunity to have a feel of the metro train when a model will be shipped next month. The model, which is under construction, in Brazil will be kept in the yard constructed in Koyambedu. The production of the trains in Sao Paulo is progressing well in the Alstom factory. The stainless steel shell of six cars in already completed and fitment of thermal insulation and other equipment is in progress. CMRL officials have witnessed the shell hold point inspections and water leak. Materials sampled by CMRL which will be brought to Chennai and tested for compliance with the specific parameters.
Meanwhile, the test to prove structural integrity of car floor under fire has been successfully completed in Europe. Similarly, the inspection of mock-up of driver’s cabin of the train has been completed by Metro Rail officials. This will be transported to Chennai for display.