ANALISIS TIPE FASE DAN DAMPAKNYA TERHADAP KAPASITAS SIMPANG (STUDI KASUS: SIMPANG TIRTONADI)

The Tirtonadi intersection, located in Surakarta, is one of the signalized intersections that poses a predicament. The predicament in question is that frequent occurrence of congestion caused by the intersection’s low capacity when compared to the volume of traffic passing through it. According to PKJI 2023, the capacity of signalized intersections is influenced by several factors, such as saturation flow, green time, and cycle time. Saturation flow represents the maximum traffic flow passing a stop line at an approach during a green signal. When the number of queued vehicles exceeds the capacity of the saturation flow, the performance of the intersection will decline. Meanwhile, green time and cycle time are influenced by the number of phases applied to the intersection.
Based on these circumstances, a study is required to explore the relationship between phase types and intersection capacity. The methods utilized encompass PKJI, Vissim, and the time slice method. PKJI 2023 is employed to obtain the ideal cycle time and capacity. Vissim is utilized to model and calculate the volume per time slice. The results obtained in vissim are then used to create a saturation flow graph, providing insight into the actual capacity of the intersection under examination is 2460.50 passenger cars per hour, and the phase type resulting in maximum capacity is type 2.

Key words : Capacity, saturation flow, phase type