Abstract

This paper discusses a case history of a highway tunnel located in lower Himalayas. The site information was collected primarily from geological mapping and limited site investigations carried out from tunnel portal due to inaccessible terrain conditions. The tunnel alignment, cross section, and elevations were assessed, evaluated, and designed based on the geological and geotechnical parameters ascertained from field and laboratory investigations. Numerical analysis was carried out to study stress-deformation behavior under varying ground conditions and multiple stages of excavation along with wedge stability for given joint conditions. Displacements obtained numerically were compared along with field monitoring values for crown and wall. Finally, a sensitivity analysis is carried out to ascertain impact of strength parameters on deformation and yielding of excavated tunnel face.

keywords: Numerical analysis; Geotechnical investigations; Geological mapping; Road tunnel; Field monitoring

References

1. Franzius JN and Potts DM. “In?uence of mesh geometry on three-dimensional ?nite-element analysis of tunnel excavation”. Int. J. Geomech 5.3 (2005): 256-266.
2. Goodman RE and Shi G. “Block theory and its application to rock engineering”. Prentice Hall, Englewood Cliffs, NJ (1985).
3. Grimstad E and Barton N. “Updating the Q-System for NMT”. Proc., Int. Symposium on Sprayed Concrete—Modern Use of Wet Mix Sprayed Concrete for Underground Support, Norwegian Concrete Association, Oslo, Norway (1993): 46-66.
4. Hoek E and Brown ET. “Hoek brown failure criterion 2018 edition”. J. rock mechanics and geotech (2018): 445-463.
5. Barton N. “An Engineering Assessment of Pre-Injection in Tunnelling”. Indian Rock conference by ISRMTT, Roorkee (2011).
6. Barton N, Buen B and Roald S. “Strengthening the case for grouting -Pre-Grouting for Tunnels in Jointed Rock”. Tunnels and Tunnelling International (2002): 34-39.
7. RS2 [Computer software]. Toronto, Rocscience.
8. RocLab [Computer software]. Toronto, Rocscience.
9. UNWEDGE [Computer software]. Toronto, Rocscience           
10. Usmani A., et al. “Interaction mechanism between two large rock caverns”. Int J Geomech ASCE 15.1 (2013): 06014014.

Citation

Ankur Chauhan., et al. “Analysis and Design of Road Tunnel in Lower Himalayas". Clareus Scientific Science and Engineering 1.1 (2024): 37-47.

Copyright

2024 Ankur Chauhan., et al. Licensee Clareus Scientific Publications. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.