Indore Metro's First 410-Ton TBM Launched, Underground Section Enters Shield Tunneling Phase

en.Wedoany.com Reported - On September 3, the Madhya Pradesh Metro Rail Corporation Limited (MPMRCL) launched "Narmada," the first tunnel boring machine (TBM) for the Indore Metro, at the launching shaft near Indore Airport. The machine, weighing approximately 410 tons, will bore from the airport direction toward the Bada Ganpati section, and is intended for tunnel construction of the first underground segment of Phase 1 of the Indore Metro. This launch transitions the project from the TBM delivery and assembly phase into the underground tunnel construction phase.

"Narmada" is an earth pressure balance (EPB) shield machine with a diameter of 6.61 meters. A total of four TBMs of the same specification are configured for this underground project, including two newly manufactured machines and two refurbished units, all manufactured or overhauled by TERRATEC at its factory in Thailand. The first two machines completed factory acceptance tests at the end of June and were subsequently shipped to India, originally planned to commence construction first from the launching shaft at the airport station; on September 3, "Narmada" completed its launch, establishing a project milestone linkage from equipment acceptance to on-site tunneling.

The underground works are being executed by a joint venture comprising Hindustan Construction Company (HCC) and Tata Projects, corresponding to Contract Package IN-05R. HCC previously announced a contract value of INR 21.91 billion, with the scope of works including approximately 8.65 kilometers of underground corridor and 11.32 kilometers of twin-tube shield tunnels, with HCC holding a 55% share in the joint venture. The contract scope also includes cut-and-cover sections, cross passages, ramps, and station-related civil works.

IN-05R involves the construction of seven underground stations, namely Indore Railway Station, Rajwada, Chota Ganpati, Bada Ganpati, Ramchandra Nagar, BSF/Kalani Nagar, and Airport, with the underground alignment connecting the ramp on the western side of the airport to the ramp on the eastern side of Indore Railway Station. According to Asian Development Bank project documents, this underground corridor is also a key component of the Indore Metro's connection between the airport and the central city area.

The four TBMs are required to cope with basalt formations of varying weathering degrees, such as Deccan trap rock. The machines are equipped with mixed-ground cutterheads, active earth pressure balance, and face pressure control systems. Following "Narmada's" lead in undertaking construction from the airport toward Bada Ganpati, the remaining TBMs will be progressively deployed in accordance with the twin-tube tunnel construction schedule of the underground contract package.