Fundamental diagrams of luggage-laden pedestrians ascending and descending stairs

In transportation terminals, a lot of passengers usually travel with luggage, which affects not only their mobility but also the ones who have no luggage, especially on stairs. As a result, congestion could be severer during rush hours. However, the impact of luggage on the movement characteristics of pedestrians ascending and descending stairs have not been systematically studied yet. Therefore, in this study, a series of single-file luggage-laden movement experiments under controlled laboratory conditions were performed. Trajectories have been extracted to analyze the movement features under different luggage-laden ratio scenarios. From the space–time diagram, it can be found the average stopping time gradually increases as the increase of the luggage-laden ratios. In the relationship between spatial headway and speed, two regimes are found, i.e., free regime and strongly constrained regime. The minimum descending headway is basically the same as the tread depth, while the minimum ascending headway is greater than the tread depth. The pedestrian adaptation time in the scenario of a high luggage-laden ratio is longer than that of none. Finally, in addition to longitudinal movement, with the increase of speed, pedestrian lateral sway amplitude decline rate in the descending process is faster than that in the ascending process. The impact of carrying luggage ascent and descent the stairs on pedestrian movement characteristics provided in this study is helpful not only for the calibration and verification of the pedestrian models but also for the design of pedestrian facilities in transportation terminals.