Buiding Up the Longest Tunnel in India


Robit is supplying forepoling systems and MIPL casings  for tunnel roof supporting, and rock drilling consumables for face drilling to RVNL Package – 5.

The Rishikesh–Karnaprayag Railway runs from Yog Nagari Rishikesh railway station in Rishikesh to Karnaprayag. The ₹16,200 crore project will shorten travel time from Rishikesh to Karnaprayag from 7 hours to ~2 hours. A 15-kilometre tunnel, reported to be the country’s longest, will be built between Devprayag and Lachmoli.

The proposed 125-kilometre stretch will have 12 stations, 17 tunnels and 35 bridges. The design consultancy contracts for tunnels are provided by Lombardi Engg, Yuksel, AECON.

The package 5 is being constructed by Navayuga Engineering Company Limited. It consists of 2 tunnels (Tunnel No. 9 & 10). Tunnel No. 9 from Laksh Moli to Maletha is 2.8 km and Tunnel No. 10 from Maletha to Rani Hatt is 4.1 km, including escape tunnels. The current geology found in both tunnels is RBM (soft rock with mixture of sand). The difficulties faced during forepoling and drilling were majorly due to RBM with big boulders of phyllite and quartize.

The NATM method is being used to construct the tunnel. Currently the daily advancement is 6 metres per day. We are proud to report that Robit forepoling systems together with MIPL casings  are approved at RVNL and are being successfully used by the contractor.

Contractor: Navayuga Engineering Company Limited
Design Consultancy: Lombardi Engg, Yuksel, AECON