First Mountain Tunnel breakthrough recorded for Mumbai-Ahmedabad High Speed Rail Corridor

New Delhi, India (Metro Rail Today):  In a remarkable feat of engineering prowess, the National High-Speed Rail Corporation Limited (NHSRCL) has reached a significant milestone in the development of the Mumbai-Ahmedabad High-Speed Rail corridor. Today, we celebrate the breakthrough of the first mountain tunnel, marking a momentous achievement in India's ambitious high-speed rail project. This achievement is a testament to the relentless dedication and precision of the teams involved in this groundbreaking endeavor.

A Swift 10-Month Journey

The Mumbai-Ahmedabad High-Speed Rail corridor project has made impressive strides, accomplishing the completion of its first mountain tunnel in a mere 10 months. This remarkable timeline highlights the commitment of the project's stakeholders and their unwavering determination to push the boundaries of modern rail infrastructure.

The Location: Umbergaon Taluka's Zaroli Village

Situated approximately 1 kilometer away from Zaroli Village in Umbergaon Taluka, Valsad district, Gujarat, this tunnel serves as a critical link in the high-speed rail network. Its strategic location brings improved connectivity and accessibility to the region, benefitting both travelers and local communities.

The Anatomy of the Tunnel

The mountain tunnel's structure is a marvel of engineering ingenuity, comprising not only the tunnel itself but also the tunnel portal and connecting structures, such as the tunnel entrance hood. The construction process is guided by the New Austrian Tunnelling Method (NATM), a proven technique in tunnel engineering.

The NATM Procedure

• Marking of Drill Holes: The process begins with precise markings on the tunnel face, ensuring accuracy in drilling locations.
• Drilling of Holes: Skilled technicians then proceed to drill holes as per the markings, preparing for the controlled blasting phase.
• Charging of Explosives: Expert handling of explosives is crucial in this phase, setting the stage for the controlled blast.
• Controlled Blasting: This critical step involves a precisely orchestrated blast to dislodge rock pieces within the tunnel.
• Removal of Muck: Following the blast, meticulous muck removal is carried out to clear the tunnel's interior.
• Installation of Primary Support: To fortify the tunnel, primary support is installed, including steel ribs, lattice girders, shotcrete, and rock bolts, customized based on the rock type identified by geologists post-blast.

Key Features of the Mountain Tunnel

• Total Tunnel Length: 350 meters
• Tunnel Diameter: 12.6 meters
• Tunnel Height: 10.25 meters
• Tunnel Shape: Single tube horse-shoe shaped
• Number of Tracks: 2 Tracks

Looking Forward: More Tunnels on the Horizon

The Mumbai-Ahmedabad High-Speed Rail corridor envisions a total of seven mountain tunnels, all of which will be constructed using the highly effective NATM Method. This approach, which combines precision drilling, controlled blasting, and robust structural support, ensures the safety and efficiency of these vital transport passages through challenging terrain.

Conclusion

The breakthrough of the first mountain tunnel is a monumental step forward in realizing the Mumbai-Ahmedabad High-Speed Rail corridor. It symbolizes India's commitment to modernizing its transportation infrastructure and signifies the successful collaboration between experts, engineers, and visionaries in the realm of high-speed rail. As we continue this transformative journey, we anticipate even more remarkable achievements on the horizon.