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Updated: Oct 10, 2025
10:52
Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior
Published on: April 13, 2016
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Emergence of the London Millennium Bridge instability without synchronisation
Igor Belykh1,2, Mateusz Bocian3,4, Alan R Champneys5
1Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, USA. ibelykh@gsu.edu.
Nature Communications
|December 11, 2021
Summary
Pedestrian-induced bridge instability, like the Millennium Bridge, arises from average negative damping by uncorrelated walkers, not synchronization. This positive feedback initiates vibrations, challenging existing synchronization theories.
Area of Science:
- Civil Engineering
- Mechanical Engineering
- Complex Systems
Background:
- The London Millennium Bridge's instability is often cited as an example of Kuramoto synchronization.
- Existing theories suggest pedestrian synchronization causes large-amplitude vibrations.
Purpose of the Study:
- To re-evaluate the cause of pedestrian-induced bridge instability.
- To propose an alternative mechanism for the emergence of collective oscillations.
Main Methods:
- Review of observational, experimental, and modeling evidence.
- Development of a general formula to quantify the effect.
- Simulation of three mathematical models.
Main Results:
- Pedestrian coherence is a consequence, not a cause, of instability.
- Uncorrelated pedestrians generate positive feedback via negative damping, initiating vibrations.
- A general formula quantifies this effect across various bridge frequencies.
Conclusions:
- Average negative damping, not synchronization, triggers bridge instability.
- Collective, uncorrelated contributions can lead to global oscillations, offering an alternative to Kuramoto theory.
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