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Footbridge Vibrations Predicted by Stochastic Load Model

  • Lars Pedersen
  • Christian Frier
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)

Abstract

Actions of humans on footbridges may result in structural vibrations that may be annoying to bridge users potentially rendering footbridges unfit for their intended use. Hence, it is useful to make predictions of footbridge vibrational performance already at the design stage involving estimation of levels of vibrations in the footbridge. Nowadays both deterministic and stochastic approaches are available for such evaluations. The have primary focus on probability-based approaches for predicting levels of floor vibrations. The predictions involve employing Monte Carlo simulations and the initial setting up of a stochastic framework describing the action of a walking person. The paper investigates the influence of selected decisions made by the engineer when setting up the basis for the prediction of levels of vibration in the footbridge.

Keywords

Footbridge vibrations Walking loads Walking parameters Stochastic load models Serviceability-limit-state  

Nomenclature

a

Bridge acceleration

F

Walking load

f1

Bridge fundamental frequency

fs

Step frequency

i

Integer

L

Bridge length

ls

Step length

m1

Bridge modal mass

θ

Phase

Q

Modal load

t

Time

v

Pacing speed

W

Weight of pedestrian

Φ

Mode shape

α

Dynamic load factor

μ

Mean value

σ

Standard deviation

ζ1

Bridge damping ratio

Notes

Acknowledgements

This research was carried out in the framework of the project “UrbanTranquility” under the Intereg V program and the authors of this work gratefully acknowledge the European Regional Development Fund for the financial support.

References

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Copyright information

© The Society for Experimental Mechanics, Inc. 2019

Authors and Affiliations

  1. 1.Department of Civil EngineeringAalborg UniversityAalborgDenmark

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