What a way to end tunneling works! 😀
Tunnel Boring Machines S25 and S28, both Ø6.51m classic EPB machines operated by the J Kumar-CRTG JV made a historic double breakthrough yesterday at the Vinobhapuri Station’s East Shaft to mark an end to the 58.6km Pink Line’s tunneling works for the Delhi Metro’s 160 km Phase 3 project.
Prior to this event, both TBMs made a breakthrough at Ashram Station in August and September 2014 from the Hazrat Nizamuddin station, and were subsequently commissioned in early 2015 to build the last 2 tunnels of package CC-24 (Hazrat Nizamuddin-Lajpat Nagar) between Ashram and Vinobhapuri. The TBMs traveled roughly 970m over a course of 20 months from Ashram and encountered everything from loose soil to mixed face hard quartz rock conditions that required frequent interventions and repair work to the cutterheads.
Vinobhapuri’s East Shaft where the breakthrough took place – this will be covered in Google’s subsequent updates.
This is the 2nd instance of a double breakthrough taking place in India. The one prior to this was achieved in 2014 by the HCC-Samsung JV for package CC-34 at the Magenta Line’s Dabri Mor station. Watch a video on that here: [Video] Double Breakthrough at Delhi’s Dabri Mor
Incidentally, the HCC-Samsung JV later handed over both these TBMs, Riddhi (S495) and Siddhi (S496), to the CEC-CICI JV in 2015 to complete CC-04’s tunneling works where they are currently awaiting to be retrieved.
With tunneling works wrapped up, contractors on the Pink Line now need to retrieve 6 TBMs – 2 from here and 4 from the Gurdwara Shaft in north Delhi. Overall, the 160 km Phase 3 project has another 2 TBMs breakthroughs pending – 1 at the Magenta Line’s Munirka Station and another at the Hanuman Mandir Shaft in Najafgarh.
For more updates, check out Delhi section of The Metro Rail Guy!