Assembly has commenced on two Terratec rock EPB TBMs at the Goregaon–Mulund Link Road Project (GMLR) site in Mumbai.
The 14.42m-diameter machines, procured by J Kumar–NCC Private Ltd, the contractor executing the project for Brihanmumbai Municipal Corporation, are the largest ever deployed in India.
The major component of the first TBM was lowered onto its cradle on March 11 in a ceremony held at the launch site in Goregaon.
The GMLR project involves the construction of twin road tunnels connecting Film City in Goregaon East to Amar Nagar, Mulund West, passing beneath Sanjay Gandhi National Park. Each tunnel will be excavated in a single drive of approximately 5.3km, giving a combined length of 10.6km.
The tunnels will provide a critical east-west road link between Mumbai’s major arterial highways, reducing travel times between the Western and Eastern Expressways.
The two TBMs will produce a finished tunnel internal diameter of 13m – large enough to accommodate a multi-lane road configuration.
The machines are designed for the project’s demanding geological and hydrological conditions. The alignment passes through Deccan basalt and breccia formations at maximum depths of 143m and potential high working water pressures.
Each machine features two screw conveyors, a fourth-row tail brush seal, twin probe drilling for advance treatment of high water inflows, and additional dewatering systems. Excavated material will be removed via Terratec’s tunnel continuous conveyor and overland conveyor system. Segment transport will be handled by MSVs along the alignment’s -1.1% gradient.
