Measuring and Modeling Dynamic Loads Imposed by Moving Crowds
Publication: Journal of Structural Engineering
Volume 122, Issue 12
Abstract
Excessive vibrations and deflections of modern flexible structures can be imposed by crowd movements. Dynamic forces generated by moving crowds of people while walking were measured using a specially designed, large, instrumented force platform consisting of six independent honeycomb plates. Experiments were conducted for individuals and groups of two and four people. A linear regression model was used to statistically characterize the footstep load-time history. Group loads were randomly simulated using the experimental parameters affecting individual footsteps and the coherency among the people in a group. The accuracy of the group load model is verified by frequency-domain comparison of simulated and measured data for groups of four people. Based on the work presented, loads are simulated for large crowds and design live loads are suggested for structural serviceability requirements under occupant walking activities. The design live loads vary both with footstep frequency and the size of the crowd.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 122 • Issue 12 • December 1996
Pages: 1468 - 1474
Copyright
Copyright © 1996 American Society of Civil Engineers.
History
Published online: Dec 1, 1996
Published in print: Dec 1996
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