Simulation-based analysis and optimization of traffic density at signalized intersections: The case of Gaziantep

With the acceleration of urbanization, individuals' transportation needs have increased correspondingly; leading to severe serious traffic congestion, especially in metropolitan areas. Particularly during morning and evening peak hours, significant congestion emerges in urban transportation networks during commuting periods. At certain times of the day, traffic flow almost comes to a standstill, a phenomenon that becomes especially pronounced at signalized intersections. Intersections represent critical points within urban traffic systems, where traffic is both directed and experiences the most severe bottlenecks. Simulation-based approaches provide significant advantages in terms of both time and cost, as they allow system behavior to be analyzed in advance before real-word implementation. In this context, the flexible and user-friendly structure of the ARENA simulation software enables the integration of variables such as different vehicle types and turning ratios into the model, thereby facilitating a more realistic and detailed analysis of urban traffic systems. This study aims to analyze and improve the performance of two operationally interconnected signalized intersections located in the city center of Gaziantep. Real-world traffic data corresponding to the peak demand periods of the intersections were gathered. Based on parameters including vehicle arrival rates, turning ratios, and signal phases, the intersections were modeled within the simulation as a coordinated system. In this way, the impact of signal timings on the overall system could be observed, and potential improvement scenarios can be quantitatively tested. Within the scope of the study, the current conditions of the intersections were modeled using the ARENA simulation software; while the OptQuest module was employed to evaluate alternative signal timing scenarios. Consequently, the effects of different signal timings on intersection performance were examined based on indicators such as total output volume and queue length per approach. As a result, the optimal configuration(s) that increase vehicle throughput capacity were identified. The results demonstrate that reasonable adjustments in signal timings can lead to significant improvements in traffic flow, underscoring the importance of coordinated signal control. Moreover, the study provides a data-driven and replicable optimization approach for similar urban areas, offering a valuable contribution to traffic planning and management.