India’s Express Global Logistics (EXG) has handled two tunnel boring machines (TBMs) for the Patna Metro rail projects.
The TBMs weighed 450 tonnes each and will play a crucial role in in excavating tunnels for the underground stations – one will work on the at Moin Ul Haq underground metro station and the other at Gandhi Maidan underground metro station. EXG was responsible for lowering the machines into the launching shafts.
The TBMs arrived at site dismantled and had to be assembled by EXG ahead of the lowering operations.
Due to space constraints and congestion in the area, it was not feasible to use a crane to handle the cargo. Therefore, EXG deployed a skidding method using a hydraulic gantry system spanning 20 m. This was combined with precise lowering techniques using strand jacks and tower system. The TBMs were lowered 52 ft (16 m) into their designated locations within the shafts.
EXG is a member to the Worldwide Project Consortium (WWPC) in India.