Characterising randomness in human actions on civil engineering structures

Abstract

Developing reliable stochastic models of people walking and jumping is of crucial importance for accurate vibration serviceability assessment of structures such as footbridges, building floors and grandstands. To inform stochastic modelling, experiments which observe the kinetic and kinematic features of human actions should be conducted. The objective of this paper is to present a laboratory-based experimental programme designed to characterise walking and jumping actions performed on rigid surfaces by a population of 8–10 test subjects. A detailed characterisation of intrasubject variability was conducted in order to quantify randomness of parameters, such as pacing frequency, step length and step width in case of walking and the frequency, impulse area and contact ratio in case of jumping. The walking locomotion parameters on a lively surface were also monitored and compared against the benchmark data collected on a rigid surface. It was observed that an increase in the liveliness (in the vertical direction) of the supporting surface tends to lead to an increase in the intra-subject variability. In addition, it was shown that neglecting intra-subject randomness in the human-induced force could lead to significant error in calculation of the vibration response.