Midblock Pedestrian Crash Predictions in a Systemic, Risk-Based Pedestrian Safety Process
Wesley Kumfer, UNC Highway Safety Research CenterShow Abstract
Libby Thomas, UNC Highway Safety Research Center
Laura Sandt, UNC Highway Safety Research Center
Bo Lan, UNC Highway Safety Research Center
Although pedestrian fatalities and injuries decreased for decades at a rate similar to vehicular occupant fatalities in the United States, recent years have seen substantial increases in the pedestrian fatality counts and rate. Most concerning is that the growth in pedestrian fatalities seems to be outstripping any gains in safety. There may be many contributing factors to this increased fatality rate, including changes in population dynamics, vehicular design, or travel trends, but under more traditional, crash-focused roadway safety management practices, systemic patterns are difficult to discern and address. Moreover, locations of risk for pedestrians may be overlooked because important data types are not collected or analyzed at a network level, and pedestrian crashes are often relatively infrequent at specific locations. This paper presents the results of efforts to develop the data profile and analysis methods for a risk-based, systemic pedestrian safety approach. Using eight years of segment data from the entire street network of the City of Seattle, the research team developed Safety Performance Functions for two types of collisions between motor vehicles and pedestrians. These predictive models were used, in conjunction with identified risk factors and countermeasures effectiveness data to develop a systemic screening tool to identify sites that may benefit from treatment. The end goal of this research is a model process and tools that allow practitioners to identify and rank locations within a jurisdiction that are risky for pedestrians and to identify and implement effective, appropriate treatments at many such locations.
IMPROVING PEDESTRIAN HYBRID BEACON CROSSWALK BY USING UPSTREAM DETECTION STRATEGY
Zhen Yang, Nanjing Forestry UniversityShow Abstract
Baojie Wang, Chang'an University
Xingchen Yan, Nanjing Forestry University
Jianxiao Ma, Nanjing Forestry University
Wenyun Tang, Nanjing Forestry University
As traffic congestion becomes more and more severe, walking as a healthy and environmentally friendly trip mode has been revived in many cities around the world. Mid-block crosswalk (MBC) as a kind of pedestrian facility can make walking more safe and convenient. Pedestrian hybrid beacon (PHB) is one of commonly used signalized MBCs and has a wide range of applications. Currently, the signal control logic of PHB is biased toward vehicles and aiming at reducing vehicles’ unnecessary delay. This is to some extent unfair to pedestrians and may lead to pedestrians’ non-compliance behaviour. To reduce Pedestrians’ waiting time at PHB crossing, this study applied upstream detection (UD) strategy to PHB. Data were collected at two crosswalks at two time periods in the city of Nanjing through video recording. Basic simulation models were first developed in VISSIM according to current signal control methods of the two crosswalks. Next, signal control logic was adjusted to develop simulation models of PHB. Upstream detectors were then added to develop simulation models of PHB with UD strategy. Simulation models were run under five different random seeds. The results show that UD strategy for PHB reduces pedestrian delay and increase vehicle delay, but the magnitude of reduction in pedestrian delay is larger than the increase in vehicle delay. UD strategy for PHB is also found to be more effective for crosswalks with relatively short crossing length and low pedestrian volume.
Safety of Pedestrian Road-Crossing Behaviors With the Implication of Mobile Phone in a Mixed Bicycle-Pedestrian Platoon Situation at Signalized Crosswalks: Case Study of Hangzhou
Jérémie Alagbe, Zhejiang UniversityShow Abstract
Sheng Jin, Zhejiang University
Research among drivers suggests that pedestrians using mobile phones may behave riskily while crossing the road, and casual observation suggests concerning levels of pedestrian mobile-use. In China, the risk may be greater with the frequent presence of cyclists on the crosswalks disputing the way with pedestrians. An observational video based survey of about 800 pedestrians was conducted to establish rates of mobile phone use, measure pedestrian crossing behavior, and compare the safety of crossing behaviors for pedestrians using, versus not using, a mobile phone. Among females and males, pedestrians who crossed while talking/listening or texting, on a mobile phone were less likely to display caution when initiating the crossing, to look at traffic while crossing, to avoid opposite pedestrians and bicycles, or to have eyes communication with right/left-turning vehicles and on-crosswalk bicycles, compared to those not using a mobile phone. Furthermore, female pedestrians who were texting reacted more slowly to the pedestrian green (PG) display. These effects suggest that talking or listening on a mobile phone is associated with cognitive or auditory distraction, and texting is associated with decreased situation awareness, and these might undermine pedestrian safety. Messages explicitly suggesting techniques for avoiding mobile-use while road crossing may benefit pedestrian safety: problem caused by technology can be solved by technology. Keywords: Pedestrians, mobile phones, bicycles, traffic safety
Modeling Pedestrian and Motorist Behavior at Semi-Controlled Crosswalks: The Effect of a Change From 1-Way to 2-Way Street Operation
Jon Fricker, Purdue UniversityShow Abstract
Yunchang Zhang, Purdue University
A large number of crosswalks are indicated by pavement markings and signs, but are not signal-controlled. In this paper, such a location is called “semi-controlled”. At locations where such a crosswalk has moderate amounts of pedestrian and vehicle traffic, pedestrians and motorists often engage in a non-verbal “negotiation”, to determine who should proceed first. This paper describes the detailed analysis of video recordings of more than 3,400 pedestrian-motorist interactions at semi-controlled crosswalks. The study also took advantage of a conversion from one-way operation in Spring 2017 to two-way operation in Spring 2018 on the street chosen for data collection and analysis. This permitted before and after studies at the same location. The pedestrian models used mixed effects logistic regression and binary logistic regression to identify factors that influence the likelihood of a pedestrian crossing under specified conditions. The complementary motorist models used generalized ordered logistic regression to identify factors that impact a driver’s likelihood of decelerating, which was found to be a more useful factor than likelihood of yielding to pedestrian. The data showed that 56.5% of drivers slowed down or stopped for pedestrians on the one-way street. This value rose to 63.9% on the same street after it had been converted to 2-way operation. Moreover, two-way operation eliminated the effects of the presence of other vehicles on driver behavior. Relationships were found that can lead to policies and control strategies that improve the operation of such a crosswalk.
Pedestrian-Vehicle Conflict Analysis at Signalized Intersection With a Concurrent Pedestrian Phasing
Jiawei Wu, University of Central FloridaShow Abstract
Essam Radwan, University of Central Florida
Hatem Abou-Senna, University of Central Florida
Pedestrian fatalities are of major concern to transportation engineers, planners, and the public. Worldwide, more than 270,000 pedestrians lose their lives on roads each year, accounting for 22% of the total 1.24 million road traffic deaths. Half of these fatalities are at intersections. The main objective of this study is to evaluate the severity of pedestrian-vehicle conflicts with different potential risk factors at signalized intersections with a concurrent pedestrian phase using a driving simulator. A full factorial experiment was designed to study these conflicts. The potential risk factors included time of day (night vs. day), vehicle movement (right turn vs. left turn), pedestrian movement (far side vs. near side), pedestrian visibility (dark color clothes vs. bright color clothes). Fifty-nine subjects were selected to participate in this driving simulator experiment. Based on the results, night time driving impacts the minimum distance, post-encroachment time, and the minimum time-to-collision. In comparison, vehicle movement and pedestrian movement only have effects on the minimum distance and the minimum time-to-collision. Moreover, it is also found that pedestrian visibility is a significant factor that affect the minimum distance and post-encroachment time.