Crash analysis on the outer circular expressway

Abstract

The road crash analyses help to identify blackspots in the roadways specially in expressways where the vehicle speed is considerable higher. The crashes in expressways occur due to various reasons. However, it is imperative to identify such crash causes which leads to accident blackspots. Therefore, this study was conducted with the aim of identifying the blackspots of the road section of the Outer Circular Highway (Expressway)of Sri Lanka where the study area spanned for a length of 19 km. The research study analyzed the governing traffic and the road geometrical parameters which have a potential influence towards the crashes in the blackspots for the Left-Hand Side (L.H.S.) and the Right-Hand Side (R.H.S.) of the expressway. Therefore, in the research study, the most governing sub parameters, either causative or corelated in the blackspots were identified. Moreover, the results were further visualized as the overall road segment and the blackspots segments to visualize the change of crash causing factors in the blackspots. The results revealed that the causative or corelated traffic and road characteristics are similar for the L.H.S. and R.H.S. blackspots. The results are beneficial to identify the optimal road characteristics influential towards blackspot and for safe road designing to reduce potential blackspots.