
Delhi Metro has successfully achieved a significant milestone in its Phase-4 Golden Line project with a major tunnel breakthrough at Chhatarpur Mandir Station, underscores the project’s progress and the expertise involved in navigating complex urban infrastructure.
More Details:
A major tunnel breakthrough has been achieved by the Delhi Metro Rail Corporation (DMRC) at Chhatarpur Mandir Station on Phase-4, Golden Line. The completion of an underground tunnel between Chhatarpur and Chhatarpur Mandir Station on the Tughlakabad-Aerocity corridor marks a critical step forward in the expansion of the city’s metro network, enhancing connectivity and easing commutes for countless passengers.
Key Presence During Breakthrough:
The breakthrough of the Tunnel Boring Machine (TBM) at the Chhatarpur Mandir site of the Delhi Metro took place in the presence of Shri Vinai Kumar Saxena, Hon’ble Lieutenant Governor of Delhi, and Shri Kailash Gahlot, Hon’ble Transport Minister of GNCTD. Shri Naresh Kumar, Chief Secretary, GNCTD. Shri Ashish Kundra, Principal Secretary to LG, Shri Jaideep, OSD (UT), MoHUA also graced the occasion in the presence of DMRC’s MD, Dr. Vikas Kumar and other senior officials.
Details of Tunnel Breakthrough:
- A Tunnel Boring Machine (TBM) broke through this morning at Chhatarpur Mandir Station after boring an 865-metre-long tunnel. This tunnel breakthrough was achieved using a mammoth 97-metre-long TBM.
- Two parallel circular tunnels for up and down movement are being constructed on this stretch as part of the Aerocity–Tughlakabad corridor. The work on the other parallel tunnel on this section will be completed by September this year.
- This new tunnel has been constructed at an average depth of approximately 15 metres. About 618 rings have been installed in the tunnel, which has an inner diameter of 5.8 metres.
- The tunnel has been built using the proven technology of EPBM (Earth Pressure Balancing Method) with a concrete lining made of precast tunnel rings. These tunnel rings were cast at a fully mechanised casting yard set up at Mundka. The concrete segments were cured with a steam curing system to achieve early strength.
Tackle Challenges with Safety Precautions:
- The tunnelling work involved numerous challenges, such as shifting a 66 KV electrical HT line.
- Additionally, the TBM had to cross below the existing Yellow Line viaduct without disrupting Metro train operations on the Yellow Line.
- All necessary safety precautions were taken during the construction of the tunnel below the existing viaduct and built-up structures.
- Ground movements were monitored with highly sensitive instruments fixed on nearby structures, ensuring that there was no settlement anywhere.
Background:
- As part of the Phase 4 work approved so far, 40.109 kilometres of underground lines are being constructed. The Aerocity-Tughlakabad corridor has underground sections totaling 19.343 kilometres.
- A TBM is a machine used to excavate tunnels with a circular cross-section through various soil and rock strata. They can be designed to bore through anything from hard rock to sand.
- TBMs have revolutionised tunnelling work worldwide, enabling tunnels to be bored without disturbing buildings and other surface structures.
- TBMs are particularly useful for underground tunnelling work in congested urban areas. DMRC has been using TBMs for its tunnelling work since Phase 1.
- In Phase 3, when approximately 50 kilometres of underground sections were built, about 30 TBMs were deployed in the national capital.
Conclusion:
The successful tunnel breakthrough at Chhatarpur Mandir Station showcases DMRC’s engineering expertise and commitment to expanding Delhi’s metro network. This achievement not only overcomes significant construction challenges but also paves the way for enhanced connectivity and smoother commutes, reinforcing the city’s growing infrastructure.
Source: DMRC – Press Release | Images Credit: DMRC