Surmounting the geological complexities of Reasi Thrust (MBT) while Advancement of Tunnel T01 (USBRL Project), using (I)-TM: Index of Ground Structure

Tunnel construction is becoming considerably more vulnerable and demanding in Himalayan terrain. The execution of T01 is also one of the most challenging tunnels of USBRLP which has undergone difficulties, as it is excavated through significant Reasi Thrust (RT). The tunnel passes through main boundary thrust (MBT), which makes significant part of active fault system of NW Himalaya. Out of total tunnel length of 3209 m, MBT makes a portion of about 309 m, which is more susceptible to natural hazards like water infiltration and slope failures. The aligned tunnel section depicts soft and extremely challenging ground conditions due to the presence of thrust planes. We adopted most robust methodology of I-System (Index of Ground-Structure) (Bineshian, 2021a) in advancement of tunnel construction to overcome various geological discontinuities and shear zones. This research paper serves as fundamental study for futuristic methods for geotechnical engineers and structural designers who are working in soft ground as well as hard terrains with diversified structural conditions.