Abstract:
Road curvature and surface slope are known to affect vehicle dynamics and influence trajectories. On curved roadway sections, this may mean that a vehicle leaves the road at a sharper angle, impacts the barrier at a less than ideal orientation, and/or be more prone to rollover. Consequently, impacts with roadside barriers are likely to involve different distributions and magnitudes of forces on the barrier as well as the vehicle and its occupants. The objective of this effort was to use modeling and simulation to analyze the safety performance of barriers when impacted by vehicles leaving the traveled way on curved, superelevated roadway sections. The intent was to develop a better understanding of the influence of roadway curvature, superelevation, and shoulder or roadside designs on vehicle trajectories leading to impacts with barriers to evaluate barrier designs and placement practices in these situations. The analyses considered two types of vehicles, six roadway curvature and superelevations conditions, and varying shoulder configurations. Simulations were conducted for three common types of longitudinal barriers and two barrier orientation options. This paper presents some of the simulation results that were performed for some of the situations analyzed relative to MASH requirements for large and small vehicles. Simulations efforts have been completed, but efforts continue to develop recommendations for improved design, selection, and placement of barriers on curved, superelevated roadway sections.
