Effect of Interactions between Vehicles and Mid-Block Crosswalks on Traffic Flow and CO2 Emission

Julio César Pérez Sansalvador,Noureddine Lakouari,Jorge Luis Zapotecatl López,José Roberto Pérez Cruz

doi:10.3390/app112411794

Abstract

Unsignalized mid-block raised crosswalks have been adopted as inclusive transport strategies, providing humps to reduce vehicles’ speed to promote drivers to yield to pedestrians. The interaction between vehicles and pedestrians can induce local jams that can merge to become a gridlock. The purpose of this paper is to investigate the interaction between vehicles and the mid-block raised crosswalk, analyzing its effects on traffic flow, instantaneous CO2 emissions, and energy dissipation. A pedestrian–vehicle cellular automata model was developed, where a single-lane road with a mid-block raised crosswalk is considered. The lane boundaries were controlled with the injections rate (α) and extraction rate (β), while the pedestrians’ entrance was controlled with the rate (αp). The system’s phase diagram was constructed, identifying four phases: maximum current, jamming, congestion, and gridlock. All observed phase transitions are of the second order. The transition from maximum current (or jamming) phase to gridlock phase is not noticed. Moreover, since the crosswalk is a bottleneck, the gridlock phase takes place when the pedestrians’ influx exceeds a critical value (αp > 0.8). The study also revealed that the crosswalk is the main precursor of energy dissipation and CO2 emissions, whose major effects are observed during the jamming phase.

Highlights

The accelerated increase in urbanization and motorization has carried multiple challenges for traffic management
A pedestrian-vehicle cellular automaton model was developed representing open-boundary conditions with rates α for injection and β for extraction, whilst pedestrians enter from a waiting zone to the crosswalk at rate αp
It was observed that the crosswalk becomes a bottleneck due to the pedestrians’ influx, producing a vehicles reservoir that acts as an alternative injection rate that prevents the emerging of a free-flow phase, even when β is much greater than α

Summary

Introduction

The accelerated increase in urbanization and motorization has carried multiple challenges for traffic management Traffic calming devices, such as vertical/horizontal deflections, physical obstructions, and pavement markings, are deployed as an effort to reduce the negative effects of motor vehicles, altering driver behavior to improve the use conditions for non-motorized road users [1,2,3,4]. In this sense, unsignalized mid-block crosswalks have been widely adopted to constrain vehicles’ speed while encouraging drivers to yield to pedestrians. They found that capacity increases as the distance between crosswalks is reduced, and that a spacing less than 25–50 m has no benefit

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Conclusion