ASSESSMENT OF RADIUS OF CURVATURE ALONG THE EXISTING ROAD NETWORKS.

The safety of traffic on roads is greatly influenced by various geometric features such as the radius of curvature, lane width, median width, and sight distance. The radius of the curve is an important parameter, that influences sight distance, design speed, and other parameters like superelevation, etc. For smaller radius curves the sight distance available also will be less, which will increase accident risks. The lower the radius of the curve, the lesser will be the sight distance, and so higher the accident risk (Abebe, 2019). The objective of this paper is to develop a tool for assessing the radius of curvature along existing road networks. This will help in accident analysis to develop a correlation between the radius of the curvature and the number of accidents. Mapping of the radius of curvature along the existing road will be useful for evaluating the existing roads and for rating in terms of road safety based on the available sight distance and radius of curvature, for asset management systems where the radius of curvature is required to be fed into the system for identifying locations where accident risks are more (blackspots) etc. It is practically difficult to measure the radius at every curve all along the road and it takes a long time. The simplest way is to obtain the data from the "As-built" drawings. In the absence of the as-built information, it becomes extremely difficult to map the parameters of an existing network. The paper proposed a novel but simplified procedure for evaluating the radius of curvature of the existing roads. The researcher developed a VBA code that can automatically extract the radius of the curves along a path for the data obtained from Aerial LiDAR or GPS-enabled Car Dashboard Camera. The VBA code computes the existing radius along a path using coordinate geometry in the CAD environment. The paper also presents the data validation on a few roads whose geometric parameters are known from the design data. [ABSTRACT FROM AUTHOR]