Experimental calibration of a one degree of freedom biodynamic model to simulate human walking-structure interaction

Abstract

Human-structure interaction (HSI) is a key issue in the behavior of lightweight and low-damping footbridges displaying vertical bending vibration mode frequency within the range of human walking pace. To address HSI, researchers have been developing biodynamic models to represent the pedestrians moving along the structure, according to different methodologies. This paper proposes a biodynamic model based on the single degree of freedom spring-mass-damper system subjected to base excitation, as this formulation is consistent with that of the motion equations of the coupled system composed by the pedestrian and the structure. The parameters of the biodynamic model are expressed by three regression equations and were calibrated with the aid of experimental tests with pedestrians walking on a rigid platform and on a flexible one under harmonic vibration. A comparison between the obtained parameters of this biodynamic model and those of other models from the footbridge literature is presented, pointing out the differences in range variation. Finally, the results of tests conducted aiming to validate the calibrated model are compared to theoretical simulations showing good correlation.