Influence of skid resistance in microscopic simulated traffic conflicts

Abstract

The assessment of skid resistance impact on traffic safety is a complex task due to the stochastic nature of car crashes. Vehicular conflicts and traffic microscopic simulation are presented as an alternative for estimating this relation. This paper evaluates the effects of different paving techniques skid resistance in both frequency and severity of micro simulated rear-end conflicts. Firstly, frictional coefficients were estimated for conventional hot mixture asphalt (HMA), HMA with grooving (HMAg), and double asphalt surface treatment (DAST). Afterwards, different scenarios were run on micro simulator VISSIM, considering three different levels of both traffic flow and desired speed. Traffic conflicts were then collected by Surrogate Safety Assessment Model (SSAM) software. The results indicate that the more loaded scenario presented both more conflicts and lower average of deceleration rates during the conflicts. In order to verify statistical relationship of each variable evaluated on vehicular interaction severity, a three-way ANOVA was performed. Traffic flow and paving technique have shown statistical influence, also the combination of traffic flow and desired speed. This result highlights the importance of aspects related to surface conditioning, once higher magnitudes of skid resistance contribute to minimize the occurrence of traffic conflicts.