Probabilistic Assessment of Road Safety- A Case Study of Madan Bhandari Highway (Sindhuli Section)

Abstract

Road traffic accidents with large number of fatalities are recorded in Nepal, a country with challenging topography, combined with inadequate road design, poor maintenance, and lack of safety measures. Conventional approach for identifying hazardous location based on historic data is unreliable due to underreporting and randomness of the data, while expert-based approaches such as AHP are subjective and static. This study integrates Fuzzy AHP with Bayesian updating to develop a probabilistic framework that uses expert judgment with actual accident data providing a more realistic assessment of hazardous road sections. The research was conducted to identify and rank hazardous road locations within Bhiman – Katari Road Section of Madan Bhandari Highway (NH-09). This study proposes the calculation of Safety Hazard Index using Fuzzy Analytic Hierarchy Process (FAHP) method and Bayesian updating to identify and rank hazardous road sections. Field surveys were conducted to assess condition ratings which was used for the computation of the Safety Hazardous Index (SHI). The results show strong agreement between predicted risk and observed crash data, which validates the effectiveness of the proposed approach. The study provides a reliable framework for evidence-based road safety assessment and prioritization of remedial measures.