Slope Stability Evaluation Along National Highway – 05 from Parwanoo to Solan, Himachal Pradesh

One of the most important geological risks that result in human deaths and financial damage around the world is a landslide. The mountainous region of Himachal Pradesh has undergone severe landslides in the past. Intense rainfall from July to September results in intensive landslides. The road blockage problem is prevalent in this area, especially in the monsoon season. These roads serve as major transit routes for pilgrims and tourists, and play an essential role in the development of economic activity. Multiple sets of discontinuities present in the rock mass of Himalayan terrain are prone to landslides at various scales, affecting the road network of the area. The current study examines the stability of road-cut slopes along National Highway-05 (NH-05) from Parwanoo to Solan, Himachal Pradesh. A total of 5 slopes were selected for the present study. The kinematic Based on the data collected in the field, Rock mass classification was done as per Rock Mass Rating System (RMR), Rock Structure Rating (RSR), Surface Condition Rating (SCR), and Geological Strength Index (GSI). Analysis of road cut slopes satisfied the conditions of planar failure and wedge failure caused by negatively oriented discontinuities. Out of five slopes, three slopes show planar failure, and two slopes show wedge failure. After evaluation and applying rock mass characterization techniques, we observed the studied rock cut slopes in poor to fair condition. Based on the slope mass rating scheme, the slopes were classified into partially stable to unstable slopes.