Analysis of Drivers’ Speed Behavior Along Horizontal Curves of Two-Lane Rural Highways Using Driving Simulator

This study is aimed at understanding the speed behavior within the vicinity of horizontal curves. For this purpose, the speed profile data of 77 drivers along 26 curves was collected from a driving simulator. Regression model developed from this dataset indicates the curve radius and speed at tangent as the most influential parameters for driver’s speed differential behavior. Further analysis showed that more than 85th percentile drivers started reacting to the curve from a distance of 80–120 m prior to the begining of a curve. Significant speed reduction by drivers was observed prior to the begining of sharp curves (R < 150 m). However, for higher radius curves, drivers preferred to continue the speed reduction in the curve section. Hence, it is recommended to adopt speed calming measures 120 m prior to the start of a sharp curve to avoid significant speed reduction.