Geotechnical Investigation of Slopes along the National Highway (NH-1D) from Kargil to Leh, Jammu and Kashmir (India)

Abstract

The national highways arealways considered as the economic backbone of the country and have oftenassisted development work all along their routes. The National Highway (NH-1D)is the most strategic and the only all weather surface link between the twodistricts of Ladakh region (Kargil and Leh). The area under investigationexperiences high vehicular traffic, particularly between March and August, asin the remaining months the Kargil and Leh districts remain cutoff from each other due to bad weather. Inrecent years, frequent occurrences of slope failures along the highwayprimarily affect the smooth functioning of the traffic movement which severelyaffects the life of the people of the area. Strategically, this road network isvery important and plays a significant role in transportation and otheractivities. In order to ensure the stability of road network in the area, itbecomes extremely important to understand the triggering mechanism of thesefailures. The present study made an attempt in this direction and the SlopeMass Rating (SMR) method has been used for slope stability analysis atdifferent locations. The stability of the slopes was also assessed usingkinematic analysis conjointly with SMR to identify the types of failure and itspotential failure directions associated with each slope. The result obtainedafter calculating RMR from the selected facets ranges from 11 to 89 with lowervalues indicating presence of potentially unstable areas. Results have shownthat in a total of 20 facets, 65.28% belong to wedge failure, 22.26% belong to toppling failure and 12.45%belong to plane failure.