The trial run of two tunnel boring machines have started from Swargate and Civil Court Metro sites and the actual excavation work would start a few days later, after the MahaMetro officials check their various parameters and are convinced about their performance.
The tunnel boring machine (TBM) placed at Swargate would proceed towards Mandai, while the TBM at the Civil Court site would excavate the tunnel towards Kasba Peth after passing under the Mutha riverbed. The tunnels would be excavated about 18 to 25 metres below the ground surface.
The TBMs are expected to meet in the Mandai area, where they would be pulled out. Both the machines were assembled over the last couple of weeks. This is the second phase of Metro tunnel excavation. In the first phase, two TBMs completed the tunnels on the Agriculture College-Civil Court stretch.
A MahaMetro (Maharashtra Metro Rail Corporation Limited) official said the alignment of the second phase of tunnelling was ready. The work would gain momentum after the initial phase of excavation gets over. He said MahaMetro had conducted survey of the buildings along the alignment of the tunnels.
“The buildings are unlikely to be affected by the work because the digging would be done deep under the ground level. But we have put the structures in various categories and would observe the impact of the work on them,” the official said.
Hemant Sonawane, general manager (public relations), MahaMetro, said, “A detailed plan of the second phase of excavation has been prepared. The work will go ahead in a phased manner from both ends. Required technical experts and manpower are in place at both the sites. The Metro’s underground section would stretch from Agriculture College to Swargate.”
The MahaMetro has also planned to deploy the third TBM to dig the second tunnel from the Civil Court-end towards Kasba Peth. The work related to its assembling is in progress. The trials are expected to begin soon.