Quantified landslide hazard assessment based on finite element slope stability analysis for Uttarkashi–Gangnani Highway in Indian Himalayas

In the Indian Himalayan region, landslide is one of the most recurring natural disasters intimidating human lives and is detrimental to infra-structures, especially for roads or highways. Landslides occurring along the major highways need to be studied with great attention since they often claim lives of travellers and disrupt road connectivity. This calls for hazard assessment of slopes susceptible to landslide along the highways. A study on the quantified assessment of landslide hazards has been carried out along the Uttarkashi–Gangnani National Highway (NH-108) in the Uttarakhand State of India. In the present study, the vulnerable road cut- slopes along the highway were identified and quantified stability assessment was carried out through rock mass classification and finite element analysis. Based on the obtained stability grades and factor of safety values, these road cut slopes were classified into various hazard classes. Thus, the study makes an attempt to quantify the hazard level of the existing and potential landside slopes, which will be useful for landslide risk management in the region.