Chennai: The breakthrough of the final tunnel in the underground route from Washermanpet to Chennai Central was made on Friday, leading to the completion of 28 among 30 tunnels in Phase I of Chennai metro rail.
As the junction at Chennai Central buzzes with traffic each day, huge tunnel boring machines (TBMs) operated by at least 30 men were making progress each day to bring the project to a completion.
The tunnel work being complete on the 3.4 km long stretch from Washermanpet to Chennai Central took 900 days to complete, and the track laying work will start soon, said the VK Singh, Chief General Manager (Underground Construction), Chennai Metro Rail Ltd.
“Each day, using the TBM, we would be able to tunnel through 10m,” said another official. With each rotation of the TBM, a bore of 1.5m is completed. Transtonnelstroy Afcons Joint Venture carried out the work.
With the track work having started on the Nehru Park — Egmore — Central stretch, operations from CMBT to Chennai Central are expected to start by the end of this year, he added.
On the corridor 1, the 36km long stretch from airport to Thiruvottiryur, underground work is pending from Thousand Lights to AG-DMS, which is likely to begin soon. There will be two tunnels in this 2.8km stretch.
VK Singh added that since the ground beyond the concourse level was rocky and blasting was not an option, mechanised excavation of the rock was carried out.
“Unlike metros in other cities, this particular station is different as the different levels are one below the other and not adjacent,” he added.
The Chennai Central metro station
The Chennai Central metro station, sprawling over 7,0000sqm, will be having five entry and exit ways. Through subways, Moore Market Complex, Park station, Park Town MRTS station, Ripon Building, Chennai Central station, Rajiv Gandhi General Hospital will be connected to the metro station.
Unlike other metro stations, this station will have a length of 388m and the width of 29m. This is to accommodate an extra track on each level. On level 1, an empty metro train will be parked, as it will be a terminal station for Corridor 2.
On level 2, one more rake will be present to manage the frequency on Corridor 1. As people can change trains at this station, it has a crossover from one line to another.
The area from Raja Muthiah Road to RGGGH will be connected underground through a series of subways. In the next two months, the 9m wide subway between MMC and Park station will be operational. Within the next four months, the subway between Park station (near Buckingham Canal’s one end) till Chennai Central will be ready.
