Part of the 23.6-km Golden Line, the tunnel breakthrough marks progress on one of the corridor’s 19.3 km of underground sections, which will connect 15 metro stations upon completion.

The 91-metre-long TBM completed a 792-metre tunnel stretch designed for up and down train movement. The work is being executed by civil contractor Afcons Infrastructure.

Constructed at an average depth of 18 metres, the tunnel features 559 precast concrete rings, each with an internal diameter of 5.8 metres. These segments were manufactured at a mechanised casting yard in Mundka and steam-cured for accelerated strength development.

“The tunnel was built using the proven Earth Pressure Balancing Method, with concrete rings cast and cured at a fully mechanised facility,” said Anuj Dayal, principal executive director of corporate communications at DMRC.

To ensure the safety of nearby structures, DMRC used sensitive instruments to monitor ground movement throughout construction. No structural settlement was reported, affirming the effectiveness of the monitoring system.

This development is part of the broader 40.1 km of underground metro lines currently under construction in Phase IV. Since Phase I, TBMs have played a key role in DMRC’s tunnelling operations, especially in congested urban zones. In Phase III, nearly 50 km of tunnels were built using 30 TBMs, enabling efficient underground expansion with minimal surface disruption.

News source: The Daily Jagran