Stochastic model of near-periodic vertical loads due to humans walking

Abstract

A mathematical model has been developed to generate realistic synthetic vertical force signals induced by people walking. This model is both stochastic and narrow-band, which are the two essential features of walking loading not addressed adequately in the existing design guidelines for pedestrian structures, such as footbridges, long-span floors and staircases. The key reasons for this are (1) the lack of a comprehensive database of walking forces in the form of continuously recorded time series that can be used for development of statistically reliable characterisation of these forces for application in the civil engineering context, and (2) the lack of an adequate modelling strategy which can account for their narrow-band nature. This paper addresses both issues by establishing a large database of measured walking time series recorded by an instrumented treadmill, while the modelling strategy was motivated by the existing numerical generator of electrocardiogram (ECG) signals and speech recognition techniques. Hence, the new approach presented in this paper can serve as a framework for a more thorough and realistic treatment of vertical forces induced by people walking that could be adopted in the design practice.