A participatory approach to determine the use of road cut slope design guidelines in Nepal to lessen landslides

Abstract. Road cut slope failures are a type of landslide process and are extensive across the road network of Nepal. In response to the pressing need for improved road cut slope design guidelines to help prevent these failures, this study employs a participatory approach to assess the efficacy of the current guidelines in Nepal and identify critical areas for enhancement. We organized a one-day workshop with 34 participants, conducted six semi-structured interviews and five unstructured interviews, facilitated two one-hour focus groups, and distributed 19 questionnaires. Participants in this research included local, provincial, and central government engineers, consultants, and academics. We conducted a thematic analysis of the qualitative data. Our findings reveal significant inconsistency in guideline adherence, attributed to their lack of user-friendliness, inconsistent recommendations, and inadequate training for engineers. We found that engineers at provincial and local levels often resort to empirical methods when designing cut slopes due to constraints such as land acquisition difficulties. Moreover, the absence of comprehensive geotechnical investigation further exacerbates the unreliability of slope designs. To address these challenges, we propose the development of new, contextually appropriate guidelines that prioritize simplicity, accessibility, and practicality for field application. We suggest that a programme of training is conducted with all Nepali road engineers with the publication of new guidelines. Through these measures, this study aims to lessen road cut slope failures in Nepal, thereby, enhancing the resilience of the road network.