MODELING OF FREEWAY RAMP MERGING PROCESS OBSERVED DURING TRAFFIC CONGESTION

摘要

This work focuses on modeling vehicle acceleration-deceleration behavior during freeway and ramp merging maneuvers under congested traffic situation. On the Tokyo Metropolitan Expressway, traffic congestion frequently occurs at merging bottleneck sections. There have been only a few research studies concerned with the traffic behavior and characteristics in these situations. Therefore, a three years extensive study has been undertaken to investigate traffic behavior and characteristics during traffic merging processes under congested traffic flow in order to design a safer and less congested merging points as well as a more efficient control at these bottleneck sections. The overall research approach is illustrated in Figure 1, emphasizing the second component, which represents this work. Sets of data capturing a wide range of information were collected using a videotape and image processing techniques. Comprehensive traffic surveys were conducted at two entrance ramps in the Tokyo Metropolitan Expressway. These data provided the fundamental information for investigating the ramp driver merging behavior. A theoretical framework for modeling ramp driver acceleration-deceleration behavior is presented. It uses the stimuli-response concept as a basic rule and is formulated as a modified form of the conventional car-following models. The collected data are used to calibrate the proposed model. The results indicate that on average 0.66 sec time gap exist before ramp drivers respond to stimuli. It is found that the surrounding