Exploring Braess' paradox in pedestrian evacuation traffic: experiment and modeling
Abstract
The emergence of the Braess' paradox in road traffic systems demonstrates the positive effect of transportation planning in improving efficiency. By contrast, the phenomenon has rarely been examined in pedestrian evacuation traffic. Yet the possibility that Braess' paradox could lengthen evacuation times under hazardous conditions has received little systematic attention. In this paper, we investigate Braess' paradox in pedestrian evacuation traffic through a series of supervised experiments and corresponding traffic assignment models to examine its potential occurrence. Our empirical and modeling results indicate that Braess' paradox is unlikely to be a prevalent phenomenon in pedestrian traffic systems. Specifically, under autonomous evacuation and the assumption of complete network knowledge, the paradox does not arise in high-demand evacuation contexts in our case studies. Under a more realistic assumption of limited network knowledge, however, the paradox can occur. These findings highlight the importance of information conditions for evacuation performance and provide guidance for the design and management of large public venues.