The HCC-Samsung Joint Venture, working on Delhi Metro’s Phase III expansion, has made a rare double TBM breakthrough, when “Riddhi” and “Siddhi” broke through at the same time at Dabari More Station.
The machines were engaged in constructing twin 5.8m i.d. tunnels on the 4.5km underground metro line between Janakpuri West and Palam Metro Stations of Delhi Metro. The construction of three underground Metro Stations at Janakpuri West, Dabri Mor and Dashrathpuri are also included in the contract. The work was awarded to HCC-Samsung JV in February 2013.
This is the first double TBM break through in India and only the second in the World, the first such being recorded during work on the 8.6km Toronto-York Spadina subway extension in 2002.
HCC has deployed four TBMs for construction of the tunnels namely Riddi, Siddi, Jantar and Mantar.
The construction sequence commenced from Janakpuri West underground station from where two TBMs – Riddhi and Siddhi -were deployed. These TBMs emerged from Dabari Mor station today. From here they will be lifted and deployed at Dashrathpuri Station where they will bore the twin tunnels to Dabari Mor station.
Simultaneously, the second set of TBMs, Jantar and Mantar, were deployed from a shaft at Vikarpuri. They will emerge from Janakpuri West underground station, lifted and deployed from Dashrathpuri station for the second boring sequence to Palam Station.