Delhi Metro Phase IV: Breakthrough Achieved On 2.2-Km Tunnel Between Janakpuri West And Keshopur

The work on Janakpuri West-RK Ashram Marg corridor under Phase-4 of Delhi Metro network is gearing up swiftly.

The line got a major breakthrough on 19 November by successfully boring a 1.4-km-long tunnel, as part of a 2.2-km-long underground section, from Janakpuri West to Keshopur with the help of a 73-m-long Tunnel Boring Machine (TBM).

“This tunnel breakthrough was achieved using a mammoth 73-m-long TBM. Two parallel circular tunnels for up and down movement have now been constructed on this stretch, which is part of a 2.2-km-long underground section from Janakpuri West to Keshopur" said a press release.

The work on the other parallel tunnel on this section was completed in December last year.

The completion of this stretch is a major construction milestone for the Delhi Metro Rail Corporation (DMRC) as the work was repeatedly halted due to the COVID-19 pandemic.

Janakpuri West-RK Ashram Marg Corridor

The Janakpuri West-RK Ashram Marg corridor, extends the operational Magenta Line from Botanical Garden to Janakpuri West.

The 29-km line will connect the Janakpuri West metro station on the Magenta line and the RK Ashram station on the Blue line.

The Janakpuri-RK Ashram stretch will run through Haiderpur, Sadar Bazar, Azadpur, Bhalswa, Pushpanjali Enclave, Mangolpuri and Paschim Vihar and will have underground sections of 9.41 km in total.

70 Per Cent Work Completed

This new tunnel stretch is a continuation of the earlier Magenta line tunnel that was constructed for the presently operational Botanical Garden-Janakpuri West corridor.

The tunnel has been constructed approximately at a depth of 14m to 16m.

On this underground stretch, apart from the twin tunnels, the ramp and the entry/exit have been completed, while about 70 per cent of the Krishna Park Extension station has also been completed.

Civil work of this particular underground section will be completed by early next year though the entire Janakpuri West-RK Ashram Marg corridor will be ready by September 2025.

Long Association With TBMs

A TBM is a machine used to excavate tunnels, with a circular cross-section, through a variety of soil and rock strata. They can be designed to bore through anything from hard rock to sand.

TBMs have revolutionized the way tunneling work is done worldwide as tunnels can now be bored without disturbing the buildings and other structures on the surface.

TBMs are especially useful for underground tunneling work in congested urban areas.

DMRC has been using TBMs for its tunneling work since Phase-1. In Phase-3, when about 50 km of underground sections were built, about 30 TBMs were pressed into service in the national capital.