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Engineering

Managing Thermal Expansion in a Long-Span Steel Arch Bridge Deck

Quick fact

A 1,000-meter steel bridge deck can expand by about 12 centimeters over a 50°C temperature change, and without expansion joints, this would generate enormous internal stresses capable of buckling the structure.

Why this is interesting

On a hot summer day, the deck of a long steel arch bridge can be several centimeters longer than on a cold winter night. How do engineers let the bridge 'breathe' without falling apart?