Delhi Metro Phase-4: Tunnel breakthrough achieved at IGNOU station for Golden Line

The Delhi Metro Rail Corporation (DMRC) has successfully completed tunnelling work for its deepest underground stretch in Phase 4 with a TBM breakthrough at IGNOU Station on the Aerocity–Tughlakabad corridor (Golden Line). The 1460-meter tunnel, built using EPBM technology, marks a major milestone in Delhi Metro’s expansion, overcoming geological challenges with precision engineering.

Tunnelling Details:

The newly completed tunnel, extending 1460 meters, was constructed at an average depth of 27 meters, reaching a maximum of 39 meters. The tunnel comprises 1048 rings, each with an inner diameter of 5.8 meters. The project employed the Earth Pressure Balancing Method (EPBM), with tunnel rings cast at a dedicated facility in Mundka.

Challenges and Engineering Excellence:

• The tunnelling drive encountered complex geological conditions, including mica and hard rock, which necessitated the replacement of a damaged screw auger.
• Additionally, working beneath existing viaducts and built-up structures required meticulous safety measures, including real-time monitoring of ground movements to prevent settlement.

Significance in Metro Expansion:

• This breakthrough marks the third TBM success in the last four weeks, showcasing the rapid progress of Phase 4’s underground works.
• The Aerocity-Tughlakabad corridor includes 19.343 km of underground sections, contributing to a total of 40.109 km of underground metro construction in Phase 4.

Conclusion:

The completion of the IGNOU Station tunnel underscores DMRC’s engineering prowess and commitment to seamless urban transport. Overcoming significant geological and logistical challenges, this milestone highlights Delhi Metro’s ongoing expansion, ensuring enhanced connectivity. With more breakthroughs ahead, DMRC continues to redefine metro infrastructure in India’s capital city.

Source: DMRC – Press Release | Images Credit: DMRC