Which destabilizing effect occurred on rope bridges when periodic, synchronized marching patterns occurred in pre-industrial armies?

💡 Explanation

Resonance frequently caused devastating bridge failures because synchronized steps induced oscillations via positive feedback. The increasing AMPLITUDE of these oscillations exceeded the bridge's material yield strength, therefore failure always resulted, rather than the other failure modes.

• Which agricultural outcome resulted from terraced hillside cultivation in the Andes?
• Which outcome occurs when medieval castle curtain walls experience prolonged foundation settlement?
• Which defensive outcome was achieved by Roman fortifications incorporating “Punic Moats”?
• Which weathering outcome increases in Mughal pietra dura architecture when rising damp transports salts?
• Which benefit results from the practice of regularly 'silt-layering' in chinampa agriculture?
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