Abstract:Driving simulation software was used to design and implement the simulation experiment of horizontal curve of passenger car expressway. Then, the driving characteristics of horizontal curve were analyzed. It is shown that all horizontal curves with different radii satisfy the consistency of absolute speed change and absolute speed gradient. The starting points and returning points of small-radius curves lag significantly, which are 100 m later than the tangent-to-spiral points and 30 m later than the spiral-to-tangent points, respectively. Additionally, the operation load is mainly affected by curvature variation. Horizontal curves with different turns and radii cause inner and outer lane departures. As the radius decreases, the departures increase and concentrate toward inside of the curve with a more stable lateral position.