New Delhi: The Delhi Metro Rail Corporation (DMRC) on 7 June marked a major construction milestone with the successful breakthrough of a Tunnel Boring Machine (TBM) at Tughlakabad Railway Colony station.
This is constructed on the Aerocity-Tughlakabad corridor, also known as the Golden Line, under Delhi Metro’s Phase IV project.
The breakthrough took place in the presence of Dr Pankaj Kumar Singh, Minister for Health & Family Welfare, Transport and IT, Delhi government, alongside DMRC Managing Director Dr Vikas Kumar and other senior officials.
The TBM completed a 792-metre-long underground tunnel from Maa Anandmayee Marg to the Tughlakabad railway colony station.
Constructed at an average depth of 18 metres, the new tunnel was built using Earth Pressure Balancing Method (EPBM) technology.
It includes 566 rings, each with an inner diameter of 5.8 metres. These precast concrete rings were produced at a fully mechanised casting yard in Mundka and cured using a steam system to ensure rapid strength development.
To ensure safety and minimise impact on the surrounding environment, DMRC installed high-precision instruments to monitor ground movement beneath existing structures. Officials confirmed that no ground settlement occurred during the tunnelling.
This tunnel is one of two parallel tunnels being built to ease the up and down train movement on the Aerocity-Tughlakabad stretch.
Of the 40.1 kilometres of underground track sanctioned in Phase IV, nearly half, 19.3 kilometres, are part of the Aerocity-Tughlakabad corridor.
TBMs have long been central to DMRC’s underground expansion strategy, particularly in dense urban environments where surface disruption must be minimised.
In Phase III, nearly 50 kilometres of underground tunnels were constructed using around 30 TBMs.
