Which structural weakness made Roman timber-framed fortifications vulnerable to siege during winter campaigns?

💡 Explanation

During winter, low temperatures cause timber in Roman fortifications to become brittle due to decreased ductility, making it susceptible to fracture under impact from ballista projectiles, increasing siege effectiveness. Therefore brittle fracture occurs, rather than biological rotting, warpage stress increases, or flammability vulnerability which involve separate environmental factors or mechanisms.

• Which risk increases when accumulated rainwater cannot drain properly from a ziggurat's terraces?
• Which mechanical consequence occurred when early steam engine boilers exceeded their design pressure limits?
• Which structural failure mode became a critical limitation for Roman ballista effectiveness with increased bowstring tension?
• Which simplification was enabled by the introduction of symbolic algebra during the Islamic Golden Age in astronomical calculations?
• Which mechanism limited the maximum size of pre-industrial water wheels used for power generation?
• Which increased risk arose when Roman roads enabled rapid troop deployment?