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This paper investigated variations in accepted gaps and lane change duration on arterial under recurrent and non-recurrent congestion. Descriptive statistics and best-fit distributions were obtained for the two parameters for both traffic conditions. Hypothesis testing using Mann-Whitney U-Test showed that the means of accepted gaps and lane change durations were statistically different between the two types of traffic conditions. The study found that during non-recurrent congestion, drivers on an average accepted smaller gaps but took longer lane change durations. Based on the fact that the data were collected for the same flow-rate (70-90 vehicles/minute) in both traffic conditions and based on the literature, the reason for the above findings could be that, drivers get more frustrated during non-recurring congestion that they accept smaller gaps. Drivers visiting the study location for game day (non-recurrent) exhibit different driver behavioral characteristics when compared to regular commuters (recurrent) which could have also contributed to the statistical differences in the lane changing characteristics of two types of congestion. These findings have direct implications on the lane changing parameters used in microscopic traffic simulation and also help transportation planners and managers to understand driver behavior during recurrent and non-recurrent congestion and better manage the facilities. [ABSTRACT FROM AUTHOR]

This paper explores potential driver behavior changes due to the interactions with advanced vehicle technologies emerging on the market. These technologies, called Advanced Driver Assistance Systems (ADAS) can take control over specific functions of the vehicle, and provide warnings to assist drivers in a variety of driving tasks. These technologies were designed mainly to improve roadway safety and provide comfort to drivers. There is evidence that these systems may change the way drivers behave on the road, resulting in traffic operational improvements and congestion mitigation, but a limited amount of research has been conducted to assess these potential impacts. This study evaluated performance measures of a vehicle equipped with two types of ADAS in a driving simulator (STISIM Drive) environment. Two systems, which are more likely to affect traffic operations, were evaluated: Adaptive Cruise Control (ACC) and Lane Change Assist (LCA). A specific route was created in the driving simulator, which consisted of an arterial section followed by a freeway. This route was driven twice by drivers: first without the systems and secondly using the two ADAS. There were a total of 25 participants with varying characteristics and backgrounds. Performance measures such as speed, lane change maneuvers, and headway with the front vehicle were collected. The analysis compared driver performance for different driver groups as well as for the entire sample. Peformance without the systems was compared to that obtained while the systems were used. Results showed changes in driving behavior due to the systems and specific driver's characteristics that are more likely to be affected by these technologies. [ABSTRACT FROM AUTHOR]