On 31.01.2019 Mumbai Metro Rail Corporation (MMRC) witnessed a twin tunnel breakthrough of the third and fourth TBM of Colaba-Bandra-SEEPZ Metro3 corridor at Dadar Metro Station.

Krishna 1, the TBM EPB, which was lowered on the 21.09.2017 from the Nayanagar launching shaft completed its tunnel drive of 2490 m as part of package 4 breaking through at Dadar metro station.

Krishna 2, the TBM EPB lowered on the 18.10.2017 from Nayanagar launching shaft completed its tunnel drive of 2472 metres also part of package 4 at Dadar metro station as well.

Krishna 1 & 2 made their way through a rocky strata made of Basalt grade 3 & 2, breccia grade 4, 3 & 2 and tuff grade 4 & 3 drilling relentlessly for exactly 506 and 479days respectively. They charted their course from Nayanagar launching shaft. The 108 m long Krishna 1 bored, on an average, 10 to 12 m daily shaping the tunnel with 1779 RCC cement rings, whereas The 108 m long Krishna 2 bored, on an average, 10 to 12 m daily, with 1766 RCC cement rings.

MMRC, as of today, has completed about 18 km of tunnelling. MMRC have commissioned 17 TBMs which have been in ten different TBM shafts. Overall 35% work has been completed. Click here for the video, here and in/77 for tunnelbuilder archive. Visit https://www.mmrcl.com. 05/19.