Which outcome results when exceeding design limits of a Roman arch bridge built with pozzolanic concrete?

💡 Explanation

When the design load of a Roman arch bridge is exceeded, horizontal thrust increases because the arch attempts to flatten, leading to outward forces at the abutments exceeding their capacity. Therefore abutment failure results, rather than concrete carbonation, keystone slippage, or wall collapse, which have different primary causes.

• Which structural weakness increased in wooden sailing ships as lumber was harvested from increasingly distant sources?
• Which design constraint primarily forced early hot air balloons to use large, lightweight envelopes?
• On ancient Roman roads, which risk increases as road base aggregate suffers compaction from ongoing heavy traffic?
• Which structural failure mode was most increased when underminng Roman fortifications during sieges?
• Which function did the 'sinus versus' (versed sine) serve in calculations using medieval astrolabes?
• Which mechanism caused widespread failures in early de Havilland Comet jetliners experiencing rapid ascents?