Probabilistic Modeling of Walking Excitation for Building Floors
Publication: Journal of Performance of Constructed Facilities
Volume 23, Issue 3
Abstract
Slender floor structures are becoming increasingly prone to excessive vibration due to human-induced walking excitation. To prevent discomfort of floor occupants and/or malfunctioning of sensitive equipment, it is necessary to have a reliable means of estimating floor vibration in the design phase. For accurate estimation of the floor vibration, both reliable excitation and structural models are required. This paper concentrates on the former by evaluating the performance of the existing force models and suggesting their improvement. For this a force model adopted in the United Kingdom by the Concrete Society was applied to four nominally identical floors using their experimentally identified modal properties. After comparison with experimental data the drawbacks of the force model were identified after which an improved model of the walking-induced dynamic force, based on the combination of two existing methodologies used separately for low- and high-frequency floors, is proposed. The improved model accounts for the intersubject variability in the walking force with respect to the pacing frequency, step length, and forcing magnitude. Moreover, it includes all relevant frequency components of the walking force into analysis, removing the need for classification of floors as low or high frequency. The proposed approach should help designers and building owners to make more informed decisions when evaluating vibration serviceability of floor structures.
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Acknowledgments
The writers acknowledge the financial support which came from the U.K. Engineering and Physical Sciences Research Council (EPSRC) under Grant Reference No. EPSRC-GBGR/S14924/01 (“Investigation of the as-built vibration performance of system built floors”) as well as Grant Reference No. EPSRC-GBGR/T03000/01 (“Stochastic approach to human-structure dynamic interaction”). The writers also thank the U.K. Precast Flooring Federation for providing the structure and technical support for the study as well as Mr. Chris Jones for proofreading the manuscript. Special thanks go to the reviewers of the paper for their valuable comments which helped to improve the original manuscript.
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Information
Published In
Journal of Performance of Constructed Facilities
Volume 23 • Issue 3 • June 2009
Pages: 132 - 143
Copyright
© 2009 ASCE.
History
Received: May 1, 2008
Accepted: Nov 17, 2008
Published online: May 15, 2009
Published in print: Jun 2009
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