Analysis capacity of U-turn movement at median opening using microsimulation PTV Vissim (case study: median opening Jl. Prof. Soedarto, SH. Tembalang, Semarang, Indonesia)

Abstract

Abstract The median opening is a facility for turning vehicles, but when traffic flow is too high can become a congestion point. Congestion due to the volume of turning vehicles turning over capacity. Based on these problems, it is necessary to know the U-turn movement capacity of the median opening. In addition, analytical capacity calculations have limitations in practical simulations similar to traffic conditions in the field. The purpose of this study was to compare the capacity of U-turn movement of light vehicle (LV) at median opening using two methods, that is, Harder model and PTV Vissim microsimulation which was validated by the capacity of field measurements. Two median opening located on Jl. Prof. Soedarto, S.H., Tembalang, Semarang, that is, Polines and Tembalang exit toll median opening, were selected as case studies. The results showed that the PTV Vissim microsimulation could outperform the Harder model in estimating the capacity of U-turn movement for LV vehicles at median opening. The inconsistent behavior of the drivers when they make U-turn, together with the geometry of the median openings, contributed to the significant errors produced by Harder model.