This paper deals with vehicular flow characteristics, especially in a congested area, from a macroscopic and microscopic point of view. Data on traffic flow have been collected on Tokyo expressways by means of vehicle detectors, cine cameras and aerial photography. Car-following spacings were measured by means of a test car method and roadside cine cameras on Tokyo expressways. A car-following experiment involving 29 cars was conducted on a test track. Various features of vehicle flow were highlighted such as oscillation characteristics in the congested area and discrepancy in traffic flow density. Speed-spacing relationships were shown to exist between free flow and congested flow areas. A qualitative hypothesis is presented to explain why and how oscillations are generated. For the covering abstract of the symposium see IRRD 284351.
Samenvatting