DMRC Completes Tunnelling Between Chhatarpur Mandir And IGNOU Metro Stations

The tunnel was constructed using the EPBM (Earth Pressure Balancing Method) technology, in which concrete lining of precast tunnel rings, from Mundka yard, was done.

New Delhi: With the completion of the underground tunnel for the Golden Line metro stations between Chhatarpur Mandir and IGNOU on Tuesday, the Delhi Metro Rail Corporation (DMRC) has achieved yet another feat in Phase IV metro extension work.

This one of the deepest tunnels was bored with a 97-meter-long tunnel-boring machine (TBM). The tunnel was constructed using the EPBM (Earth Pressure Balancing Method) technology, in which concrete lining of precast tunnel rings was done. These rings were prepared in the automated casting yard set up in Mundka. Quick strength was provided through a steam curing system.

The tunnelling started in 2023 but faced several hurdles like steep slopes and hard rocks which damaged the screw auger of the TBM. DMRC followed all necessary safety measures during tunnel boring with installations of high-sensitivity equipment under the existing viaduct and surrounding structures to avert any possibility of land collapse.

About 40,109 km of underground lines are being constructed in Phase IV. Of this, 19,343 km is under the Aerocity-Tughlakabad corridor. DMRC has been using TBMs since Phase I and during Phase III, about 50 km of underground section was constructed with the deployment of 30 TBMs.

Parallel to the tunnel at IGNOU station, a second tunnel is also being built for downward movement. Its breakthrough is scheduled for March 2025. This will help in improving passenger facilities and making their journey smooth.