Avaliação de interseção do tipo rotatória no Município de Campina Grande, utilizando software de microssimulação.

Abstract

Roundabouts emerged as great solutions to solve traffic congestions in large urban centers. This solution improves traffic safety and security once it increases the intersection capacity and reduces waiting time. However, poorly designed intersections can interfere in these aspects. This research aims to analyze the operational capability and efficiency of a roundabout located in the city of Campina Grande. The study focuses mainly on the critical delay and service level of the roundabout. In order to evaluate this intersection, we build an origin-destination matrix based on the hour and day of the highest traffic flow. Data were collected using a tripod and a cellphone recording, divided into four videos of 15 minutes each. For microsimulation, we used the Vissim software and Wiedmann 74 and 99 models. From the results obtained through microsimulation, we choose the most representative model by using the number of vehicles counted at the same time-lapse as a calibration parameter. Adjusted parameters were selected based on the literature. The critical gap was selected based on data collected from the road with the most significant traffic volume in order to obtain the biggest number of accepted and rejected gaps. Besides, the critical gap was calculated using the Raff and Wu deterministic methods, while the simulation method was used to calculate other gap used in this study. According to the results obtained with the origin-destination matrix, Monday is the weekday that presents the highest traffic flow. Using the Wiedemann 74 model, the average error regarding vehicles number was 14,4%, while using the Wiedmann 99 model, the average error was only 11,8%. The deterministic methods did not show effectiveness and accuracy to determine the critical gap. Whereas, the simulation method was effective because it calculated a gap of 2.5 seconds, which means that drivers in Campina Grande are more aggressive in intersections if compared to other cities. After evaluating the simulation results into three different cases, we found that the roundabout operates at a service level B. Cases that provide the greatest service level are the ones that prioritize the main road and semaphores installed in it.