Two tunnel boring machines from Germany to be used for construction

Kolkata: Rail Vikas Nigam Limited (RVNL), the executing agency for the Purple Line which will connect Joka to Esplanade, will bring two tunnel boring machines

(TBM) from Germany for the construction work of the line beyond Majerhat.

The machines are expected to arrive in Kolkata in January 2025 and the tunnelling work may commence from March 2025.

The Joka to Majerhat stretch of the Purple Line is already functional. Construction work of Mominpur to Esplanade stretch of this Corridor has been going on. Work order for construction of this stretch was issued to Larsen and Toubro last July.

After Mominpur, four stations–Khidderpore, Victoria, Park Street and Esplanade will be underground stations. To burrow tunnels for this stretch the machines will be brought by the executing agency.

Currently, preparatory work to construct the launching shaft is going on. The construction of the D-Wall of the launching shaft was started from June 27 at St. Thomas School premises in Khidderpore. The length of this D-Wall will be 65 metres and the construction is expected to be over within two months.

Apart from that, the casting work of the tunnel segments was started at the casting yard at Sarkarpool in Maheshtala. Width of each segment, which will be used in the tunnels, is 1.40 metres and six such segments will be needed.

The TBM machines, after boring the tunnels, will fix the lining with these pre-cast segments under the ground to give it a final shape.