The influence of spatial parameters on pedestrian lateral loading.

Abstract

Dynamic loading from pedestrians walking on flexible structures such as footbridges is the subject of much research at present. The interest is stimulated by several notable instances of uncomfortable perceptible vibrations on prominent footbridges in the recent past. Some of this research has revealed that the phenomenon is not entirely due to modern construction techniques with examples of pedestrian-induced vibrations from as early as the 1600s being reported. Such pedestrian-induced vibrations can occur in vertical and lateral directions with the latter being the focus of this paper. Recently published international design guidelines; e.g., Eurocode 5 (NSAI, 2005), ISO 10137 (2007), Setra (2006), FIB (2005), and Hivoss (2008) direct the designer to estimate the response of the footbridge due to crossing pedestrians, and then to measure this against prescribed limits set out either directly or indirectly by the guidelines. Some of these guidelines provide force functions to simulate pedestrian loading, while others are less prescriptive. The load functions that are provided tend to be deterministic in nature and have been shown to be deficient in accurately modelling actual pedestrian loading. Consequently, research is currently being conducted into the exact nature of pedestrian loading and the parameters which influence it. Previous research by the authors has examined the impact of walking velocity and pacing frequency on both vertical and lateral loading. This paper presents the results of recent walking trials, conducted along an 11m walkway to investigate the influence of spatial parameters on pedestrian lateral loading.