Search

Surrogate safety measures (SSM) as indicators of accidents are useful tools in safety evaluations. Nowadays, developing intelligent vehicles without drivers in order to reduce the human errors is a popular topic in civil engineering. Such vehicles are equipped with intelligent collision avoidance systems (CAS), in which safety indicators are applied as warning strategies. Heretofore, different safety indicators have been developed, but most of them are suitable for rear-end conflicts. In this paper, a new framework is proposed to calculate the risk of sideswipe collisions at each instant based on SSM. For this purpose, time-to-collision (TTC) and post-encroachment time (PET), as the most important time-based indicators would be applied and a new method would be presented to calculate these indicators. The application of the framework is illustrated by microscopic traffic data for an arterial road. In all, the new framework has three main applications: 1- As a warning strategy for CAS, 2- Specifying dangerous positions and 3- Identifying aggressive drivers. [ABSTRACT FROM AUTHOR]

In this paper we proposed method for assessing pedestrian risk at the signalized pedestrian crossing equipped with counter. Results showed that 17.5% of pedestrians were at high risk and male pedestrians are more often in dangerous situation (20.4%) than female pedestrians (14.4%). About 3% of all examined pedestrians created conflict situations, more frequently in first 5 seconds and last 5 seconds of red light phase (79.7% of all offenders), but the risk that pedestrians will create a conflict situation were higher in other time of red light phase. Analysis of pedestrians' behavior at pedestrian crossings equipped with countdown display could point to potentially safety problems for pedestrians and those analysis could give direction for proposing and implementing adequate countermeasures. Also, numerically defined pedestrian accident risk could assess road safety level for pedestrians and show accident occurrence probability. [ABSTRACT FROM AUTHOR]