Empirical Study of Lane Changing in Urban Streets under Varying Traffic Conditions

This paper investigated the variations in accepted gaps and lane change durations with respect to different traffic flow rates on urban street. Data for accepted gaps and lane change durations were collected during the peak, off peak, and mid-day hours on normal working days to cover flow rates ranging from free flow to congested conditions. Descriptive statistics and best fit distributions were obtained for the collected data. Hypothesis testing using Mann-Whitney U Test proved that the mean size of accepted gaps was statistically different between free flow and congested conditions. The best fit distributions showed that a considerable number of drivers accepted smaller gaps during congested traffic conditions than in free flow conditions. However, lane change durations did not show any statistical difference between different flow rates. The findings from this study have direct implications on the gap acceptance and lane changing parameters used in microscopic traffic simulation, particularly during model calibration.