Last week 4-years of work reached a significant milestone on the 4-lane Delhi-Vadodara Expressway tunnel breaking through the pilot heading.
Whilst just another tunnel breakthrough, this one involved excavating two 4km long, 22m span caverns and 10no. cross-passages through very poor fissile shales with low cover at the portals, a sandstone and siltstone hillside with limestone bands containing karst cavities charged with surface water having > 100m head.
The final hurdle was excavating this below an existing stream down to 10m of cover and a face of water-bearing mudstones and clays.
It’s been an immense slog, and whilst the team celebrates this milestone, let us not forget that just recently 8 miners lost their lives in a tunnel collapse in Telanaga and the same time last year in Uttarakhand 40 miners were trapped due to tunnel collapse.
This achievement should equally celebrate the doggedness of the people on site that stood firm against pressures of production to safely overcome these engineering challenges whilst ensuring the miners went home safe every day.
Our hope is the Indian tunnelling community take pride in building this tunnel and we can share the ups and downs to improve tunnelling practice in India, and so achieve safe and high quality tunnels and adopt some of the ‘western innovations’ bought to this project.
Some pictures of the tunnels being enlarged in sequence, cross-passages, secondary lining, design and analysis that went in to identifying all risks and mitigating them prior to construction are shared here.
Well done to all those that take pride in their work and the safety of others. Keep going guys and gals. It’s not over yet!
Ask any questions on LinkedIn: https://www.linkedin.com/posts/bedi-consulting-ltd_last-week-4-years-of-work-reached-a-significant-activity-7302687332833329154-uBO1?utm_source=share&utm_medium=member_desktop&rcm=ACoAAAZkKHsBU-c85ZekejX4p5w8t4Cm98JtLFU
