Assessing the performance of pedestrian stoop evacuation under height constraints with different motivations

Abstract

In some specific pedestrian evacuation circumstances such as where the presence of fire smoke, pedestrians are forced to take abnormal walking postures like stooping or crawling to avoid exposure to harmful smoke. Many previous studies have focused on the characteristics of pedestrians' upright walking or crawling. However, the performance of pedestrians’ stoop evacuation has not been comprehensively studied. In the present paper, a series of experiments were carried out to understand the performance of pedestrian stoop movement by considering three height constraints (H = 1.0, 1.5, and 2.0 m) and two motivation levels (normal walking and running movement). To quantificationally analyze the speed features, the trajectories of pedestrians were first extracted from video recordings. With these data, the distribution of pedestrian walking speed and the speed reduction characteristics during long-distance stoop motions were discussed. In addition, physiological indicators like blood pressure and heart rate (HR) were compared before and after the experiment. Finally, according to the collected HR data and questionnaire data, HR-based evaluation and self-reported evaluation of stoop movement intensity were discussed. The findings in this paper provide fundamental data for pedestrian stoop movement with height constraints which could be beneficial to the evacuation models and the building safety design.