A Physics-Based Analysis of Barrier Removal on the Yogyakarta Ring Road Using the LWR Traffic Flow Model

Abstract

Road separators are used to divide traffic flow so that vehicle movement becomes orderly and minimizes the possibility of accidents. Recently, proposals to remove road separators have been discussed as a strategy to address traffic violations. However, the implications of such measures on traffic-flow characteristics remain unclear and require further investigation. Traffic flow on the Yogyakarta Ring Road is analyzed using a macroscopic traffic flow approach. This study is a simulation-based quantitative investigation that employs the LWR (Lighthill–Whitham–Richards) model to examine the influence of road width, vehicle speed, and traffic flux on traffic dynamics. The concept of fluid flow is used as a qualitative analogy to support the physical interpretation of traffic behavior. This study aims to assess the impact of removing separators on traffic flow characteristics. Literature review and numerical simulations implemented in the Spyder IDE were conducted to model traffic-flow patterns by varying lane width, vehicle speed, and traffic density parameters within the LWR framework. Through three traffic flow engineering simulations, Simulation results show that different vehicle categories exhibit distinct speed and traffic-flux characteristics under varying lane-width conditions. Simulation results indicate that the removal of separators may alter traffic-flow characteristics, leading to changes in vehicle speed and traffic flux that could reduce traffic-flow efficiency under the modeled conditions.