Rekayasa simpang dengan bentuk geometri tak standar untuk peningkatan kinerja: studi kasus Simpang Tegal Gendu Kota Yogyakarta

Intersections with unconventional geometric shapes often require special treatment to operate safely at an acceptable level of service. This study examines the Tegal Gendu Intersection, a four-way signalized intersection in Yogyakarta City that has a geometric arrangement outside of what is specified in the latest edition of the Indonesian Highway Capacity Book (PKJI 2023). Using standard traffic volume surveys, geometric measurements, and signal timing observations, the study evaluates intersection performance indicators, including saturation levels, delays, queue lengths, and level of service. Traffic microsimulation modeling using PTV VISSM was then conducted to develop and test improvement scenarios. The analysis results indicate that the existing intersection operates at Level of Service F, characterized by high levels of saturation, delays, and queue lengths. Implementation of the proposed intersection separation scenarios demonstrated improved performance, reflected in reductions in delays and queue lengths across several approaches. Based on the results of alternative scenario modeling, the average delay decreased from 179.46 seconds/vehicle to 105.23 seconds/vehicle. Therefore, the proposed improvement alternatives can be considered by the relevant authorities to improve traffic performance at the Tegal Gendu Intersection.