A CASE STUDY TO REDUCE ACCIDENT RATES AND WAITING TIMES AT A SELECTED ROUNDABOUT

Abstract

In this study, the crash statistics for the roundabouts in Izmir, Turkey were analyzed. One of the roundabouts with the highest crash rates was selected and countermeasures for crash reduction at the selected roundabout were identified. The expected benefits were estimated by the use of before and after crash analysis data found in the literature. In addition to the countermeasures for crash reduction, the maximum waiting times at the roundabout were analyzed and minimized. The roundabout has 28 units of traffic signals. Phases of the traffic signals at the roundabout were evaluated for all directions and improved according to the Highway Capacity Manuel traffic signal timing formulas. The improved phases of the traffic signals were evaluated using ARENA simulation software. The maximum waiting time reduction at the roundabout was documented using the outputs of the simulation model. The fuel usage for the vehicles and the amount of emissions transmitted to the atmosphere are expected to reduce due to the reduction in the maximum waiting times at the roundabout.