2 years after Silkyara collapse, new norms could shape tunnel building, Pg13

Key Highlights:

• The Silkyara tunnel collapse on November 12, 2023, prompted the Ministry of Road Transport and Highways (MoRTH) to issue new guidelines for tunnel construction.
• The guidelines, released on December 5, aim to prevent tunnel collapses during construction on national highways.
• MoRTH found that many Detailed Project Reports (DPRs) for tunnel projects lacked necessary technical depth.
• The new guidelines mandate the preparation of a Geotechnical Baseline Report (GBR) and a risk register as part of the DPR.

Detailed Insights:

• The Silkyara Bend-Barkot Tunnel is part of the Char Dham Mahamarg Pariyojana on the Dharasu-Yamunotri highway section of NH 134.
• Road tunnels are essential for providing seamless passage in difficult terrains like mountainous regions and eco-sensitive areas.
• The project in-charge will be responsible for verifying the accuracy of geological and geotechnical investigations in the DPR.
• The risk register should include perceived hazards, associated risks, and potential mitigation measures based on DPR studies.
• The fundamental principle of risk mitigation is that the party best equipped to manage the risk shall bear it, central to contract design.
• Detailed design and proper implementation are crucial for tunnel projects because the ground serves as a support system.
• These guidelines are important in light of MoRTH’s initiative to extend the road network to border areas.

Key Concepts Involved:

• Detailed Project Report (DPR): A comprehensive report containing all the technical details of a road project.
• Geotechnical Baseline Report (GBR): A report that establishes the expected geological and geotechnical conditions for a tunnel project.
• Risk Register: A document that identifies potential hazards and risks associated with a project and outlines mitigation measures.