Synchronous lateral excitation

High school (ages 12+)
Science & Technology

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/synchronous-lateral-excitation

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the phenomenon classification?Dynamic structural vibration amplification due to collective pedestrian motion
2. What is the primary mechanism?Phase-locked lateral footfalls of pedestrians matching structure's natural lateral frequency
3. Why did the London Millennium Bridge wobble when it opened?Because over 100,000 people walked on it at the same time, and their side‑to‑side steps matched the bridge's natural sway, adding energy and making it shake.
4. How do engineers stop a bridge from wobbling?They add dampers, make the bridge stiffer, or use active controls to absorb the shaking energy.

Modal Properties: Characteristics of a structure's vibration, including natural frequencies and modes.
Damping Ratio: A measure of how quickly vibrations decay in a system.
Phase-Locked: When multiple oscillating systems synchronize their timing and rhythm.