In early-November, officials from the Maharashtra Metro Rail Corporation Limited, workers from the Gulermak-TATA Projects Joint Venture, and Terratec representatives celebrated the breakthrough of a 6.61m diameter Terratec EPBM, named ‘Mula’, on the Pune Metro Rail Project, in Maharashtra, India. The machine holed through into the underground Civil Court Station on Pune Metro’s 16.56km Line-1 (Purple Line).
The major milestone saw Gulermak-TATA Projects JV complete twin-tube tunnels, using two EPBMs, between the start of the ramp at chainage 10950 and a NATM section at the start of Civil Court Station at chainage 12600, a total of approximately 1650m of TBM tunnelling. The TBM’s excavated through Shivaji Nagar Station.
It was a good achievement considering the hard rock and being in a densely populated area. Also, during the difficult time of lockdown, Terratec’s field service team was available at the jobsite to support the JV team and the JV team achieved the best monthly progress of 301 metres.
In 2019, Maharashtra Metro Rail Corporation Limited (MahaMetro) announced that the joint venture had won both of the twin-tube tunnel packages on the new 16.56km-long north-south metro corridor. The 5km underground section – which runs from the College of Agriculture in Shivajinagar to Swargate and has five stations – is considered the most challenging portion of the line, as it passes under the densely populated areas of Kasba Peth, Budhwar Peth and Mandai market.
The Terratec EPBMs feature robust mixed-face dome-style cutterheads designed to work effectively in the compact Basalt that is expected on these contracts at pressures of up to 4 bar. As the TBMs progress, 1,400mm wide by 275mm thick pre-cast concrete lining rings will be installed, which consist of five segments plus a key.
Meanwhile, the city’s third TBM (S81) is expected to be launched northwards towards Mandai Station early next year with assembly commencing in December 2020.