New Delhi:
The Delhi Metro Rail Corporation on Friday commenced construction work on the underground section of its Phase 4 project, officials said.
The work began on the underground section of the 28.92 km-long Janakpuri West R K Ashram Marg corridor. This corridor consists of 7.74 km-long underground lines.
DMRC’s Managing Director Mangu Singh and other senior officials joined the event via video conferencing.
“The work commenced for the construction of D Wall at the Krishna Park Extension Metro station, and the tunnel segments shall be used for tunnelling with Tunnel Boring Machines (TBM) on a 1.4-km stretch between Janakpuri West and Keshopur,” the DMRC said in a statement.
In addition, this approximately 2 km-long stretch will also have the Krishna Park Extension Station in between, as well as a 365 m cut-and-cover open ramp near Keshopur, leading to the elevated section, it said.
D Walls or Diaphragm walls are structural concrete walls constructed in deep excavation based projects. Diaphragm walls are often used at congested sites, close to existing structures, where there is restricted headroom or where the excavation is of a depth that would otherwise require the removal of much greater volumes of soil, officials said
The excavated area is secured by these walls and then the construction work of the underground station is commenced. This technology has been used for Delhi Metro’s underground stations right since Phase 1, the DMRC said.
The tunnel segments are being cast at the state-of-the-art casting yard developed at Mundka. The casting yard will make 2,100 rings for the tunnelling work, it said.
This work was awarded last December on an Engineering, Procurement and Construction (EPC) basis, the officials said.
In spite of all the constraints, like shortage of labourers and materials due to lockdown, the milestone could be achieved on time, the DMRC statement said.
On June 24, the casting work of u-girders for this corridor was started.
The Janakpuri West-R K Ahsram Marg corridor is an extension of the Delhi Metro’s Magenta Line and will come up with 22 stations.
Construction work on this particular section had started in December.
Under Phase-4, 61.679 km of new metro lines shall be constructed across three different corridors comprising 45 metro stations. These new sections shall provide interconnectivity among the already operational sections of the DMRC network. Out of this, 22.35 km will be underground, officials said.
