Rock Slope Stability Analysis Along NH 1 in Ladakh

NH 1D has always been a national highway of high strategic importance, whether from a defence or civilian point of view. The highway connects Srinagar with Leh in Ladakh. Ladakh remains cutoff for 5–6 months from the rest of the world from November to April due to heavy snowfall at Zojila pass. The rock stability analysis along NH-1D is critical for the smooth operation of traffic flow. The major goal of this study is to carry out a geotechnical stability analysis along the NH-1D in Ladakh. The study was carried out with the help of a review of recent literature and relevant field tests. The methodology, consists of calculating the RMR (Rock Mass Rating) and SMR (Slope Mass Rating) values of the rocks, followed by their kinematic analysis. The field studies consisted of the identification of instability prone sites, the collection of discontinuity data, the assessment of groundwater conditions at 38 vulnerable locations, and the carrying out of a point load test Out of the total number of sites chosen, 29% fall into the “fair” category, while 71% fall into the “good” category. However, there are a few sites like site 8 (19.3 km), site 13 (24.9 km), site 15 (27.5 km), site 18 (30.9 km), site 27 (115.2 km), and site 29 (117.2 km) that fall under the “marginally good” category. This classification indicates that many sites are prone to slope failure and are in need of immediate measures against stability.