Contractor Soma Enterprise Limited and TERRATEC have celebrated a significant milestone in Mumbai’s ongoing water infrastructure development with the breakthrough of a 3.2m diameter Open TBM on the Amar Mahal I water transfer tunnel contract. This achievement marks a pivotal moment in the city’s ambitious water tunnel network expansion, which now surpasses 100km in total length.
The newly completed 9.7km tunnel runs from Ghatkopar to Parel via Wadala. The machine, specifically designed for the geological conditions encountered along the project alignment, features a modular design enabling both shaft launching and retrieval, ensuring flexibility during construction. Its robust cutterhead, equipped with heavy-duty back-loading disc cutters, is driven by VFD controlled electric motors capable of achieving optimal torque and exceeding 10rpm rotation speed.
To navigate the diverse geological strata, the TBM was engineered with a comprehensive ground support system, encompassing a fixed probe drilling unit, two rock bolting drills, a shotcrete pump, and a steel arch erector. These features provide vital safety and stability during the tunnelling process.
The AMT-I tunnel is one of a number of projects presently being carried out by the Municipal Corporation of Greater Mumbai (MCGM) to augment and improve its water distribution system in order to meet increased demand and ensure reliable supply.
The Amar Mahal I tunnel is a key element of MCGM’s multifaceted approach to enhancing the city’s water distribution system, addressing critical issues like leakage, contamination, encroachments, and inaccessibility. This project, consisting of two TBM drives totalling 9,683m in length, exemplifies the long-term solution of utilizing tunnels for a more reliable and efficient water supply network.
A notable feature of the TBM is its disassembly design, allowing for the removal of all components through the completed tunnel. The largest component, the cutterhead, is engineered with a flange enabling it to be dismantled into two pieces for easy extraction.
TERRATEC’s Field Service team is providing ongoing support to ensure optimum performance and successful project completion, ensuring this vital project stays on schedule.
In Feb. 2023, TERRATEC’s 3.2m diameter hard rock open gripper TBM successfully completed the Amar Mahal II Tunnel Project (AMT-II) in Maharashtra. This marks the successful completion of two drives for the 5,531m long water transfer tunnel contract, undertaken by contractor Patel Engineering Limited.
Mumbai’s water tunnel network, operating at a depth of 100-110m, provides crucial protection against contamination and sabotage. The challenges presented by falling rocks and seepage are addressed by utilizing robust final lining techniques to prevent water ingress.
Comments: