Improving the Capacity and Level of Service at the Sixth Circle in Jordan by Using Traffic Signals and Roundabout Metering Approach

Abstract

Background and Objective: This study aims to improve the capacity and level of service at the sixth circle in Jordan by using traffic signals and a roundabout metering approach. Methods: VISSIM software and C++ program were used to improve the capacity and level of service. The site area (Sixth circle) was located near Crown Plaza and the Jordan Gate Towers project, which causes congestion due to heavy traffic flow. Therefore, this paper assesses the traffic in the sixth circle and presents the possible solutions to reduce the daily traffic flow for the users of this circle. Results: Four signals were placed at the roundabout in the second scenario, which was connected to each other with different cycle lengths. 90-second cycle length gives D value of the level of service. The third scenario was placed adaptive signals on the roundabout, which connects traffic signals with ground detectors placed at a certain distance before the signal and based on the queue length of the flow cars that pass the detector. Conclusion: The adaptive signals worked on the opening and closing and were designed according to the language simulation and the adoption of the language C++. The first two signals were opened considering the Swefieh road with the reference of King Faisal for a period of 45 seconds. It was then closed for 45 seconds to open the signal from the next street from the fifth circle with Zahran street.

Modeling of Queue Detector Location at Signalized Roundabouts via VISSIM Micro-Simulation Software in Amman City, Jordan

“…Roundabouts perform well when the flows from all approaches are balanced, with platoons present in the circulating flow, and vehicles from each approach can enter the roundabout. This is because the yield rule limits the approach flows to depend on the circulating flow, and the overall roundabout performance depends on both the circulating flow and the approach flows [13][14][15]18,[22][23][24][25][26][27][28][29].…”

“…In addition, the literature on queue detectors from international countries includes research from the United States [18,37], Australia [25,28,38], Ghana [15], Portugal [24], Albania [36], Spain [41], and Egypt [16]. Meanwhile, one study in Jordan is related to roundabout metering with queue detectors [13]. Some of these studies analyzed the performance of signalized roundabouts using the standard value of the queue detector [18,37,41].…”

“…The implementation of different signalization options at all types of intersections in Jordan may offer a potential solution to address traffic congestion with imbalanced traffic flows. Several studies, including [9,[11][12][13][14], have demonstrated that signals can modify the roundabout's inherent priority rule, resulting in more evenly spaced delays. In transportation system modeling, simulation is commonly used to test the effectiveness of proposed solutions for roundabouts.…”

“…VISSIM is a highly detailed microscopic software that accurately depicts traffic dynamics. It is capable of simulating multimodal traffic flow with features such as speed zones, conflict zones, and 3D modeling, making it more complex than other software (e.g., SIDRA and AIMSUN) [3,[13][14][15][16][17][18][19]. Python is used as an interface in VISSIM to program signal control with queue detectors, which provides greater accuracy compared with other macro languages (e.g., Visual C++, JavaScript, or Visual Basic).…”

Evaluation and Improvement of Elba-House Road Intersection in Amman-Jordan

“…Comprehensive research by Al-Jabburi k. and Hamid S. (Karim Al-Jabburi, 2016) was conducted to study the Wadi-Saqra intersection in Amman, Jordan to establish a control model for the traffic flow at this intersection and improve its level of service. Another study by Khliefat I. et al (Khliefat, Naser, Alhomaidat, & Hanandeh, 2021) was carried out to improve the capacity and level of service of the sixth circle-signalized intersection in Amman. VISSIM software and C++ program were used in this study to achieve its aims.…”