Last Updated:
Out of the 40.109 kilometres of underground lines approved under Phase IV, 19.343 kilometres belong to the Aerocity-Tughlakabad corridor.
The second tunnel’s completion in early 2025 will further boost connectivity along this key route.(Photo: Financial Express)
The Delhi Metro Rail Corporation (DMRC) has successfully completed the construction of its longest underground tunnel.
This tunnel stretches between the Tughlakabad Airforce Launching Shaft and Maa Anandmayee Marg, part of the Phase-IV Tughlakabad-Aerocity corridor.
As per Times Now News, a 105-metre-long Tunnel Boring Machine (TBM) made the breakthrough at Maa Anandmayee Marg station after boring a 2.65-kilometre tunnel. This section includes two parallel circular tunnels for up and down train movement. The breakthrough for the second tunnel is expected by January 2025.
Key Details of the New Tunnel
The tunnel has been built at an average depth of around 16 metres, with nearly 1,900 rings installed to create an inner diameter of 5.8 metres. The construction faced several challenges, such as relocating a sewer line and working through hard rock layers.
The tunnel was built using the Earth Pressure Balancing Method (EPBM) technology, with concrete tunnel rings cast at a mechanised yard in Mundka. These rings were cured with steam to ensure early strength.
Safety was a top priority during the project, especially as the tunnel runs beneath existing structures. Ground movements were closely monitored using sensitive instruments to ensure the safety of nearby buildings.
As part of the Phase IV expansion, DMRC is building a total of 40.109 kilometres of underground lines, with 19.343 kilometres of these lying along the Aerocity-Tughlakabad corridor.