Which risk increased along Roman roads during winter due to repeated freeze-thaw cycles affecting roadbed materials?

💡 Explanation

When temperatures fluctuate around freezing, moisture within the roadbed undergoes cyclical phase changes which generates ice lenses due to frost heave increasing pressure within the aggregate matrix leading to cracking. Therefore cracking risks from ice lens formations increase during winter, rather than joint settlement rivets corrosion or slope instability which require continuously wetter or warmer conditions.

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