When heated to 1000 Degrees F, steel will

When heated to 1000 Degrees F, steel will

• A. Expand up to 9 1/2 inches and fail at 1000-1100 Degrees
• B. Contract slightly and remain strong
• C. Stay the same size
• D. Melt completely at 900 Degrees

Answer: (A)

Structural steel expands when heated and loses strength at elevated temperatures, which can lead to failure under load in a fire. The statement that steel expands noticeably (in the example, up to about 9 1/2 inches) and then fails in the 1000–1100°F range reflects both key effects: thermal expansion altering geometry and connections, and substantial loss of load-bearing capacity as temperature rises. Steel does not contract with heat, nor stay exactly the same size, and it does not melt at 900°F—the melting point for most structural steels is well above that (typically several hundred more degrees).

Structural steel expands when heated and loses strength at elevated temperatures, which can lead to failure under load in a fire. The statement that steel expands noticeably (in the example, up to about 9 1/2 inches) and then fails in the 1000–1100°F range reflects both key effects: thermal expansion altering geometry and connections, and substantial loss of load-bearing capacity as temperature rises.

Steel does not contract with heat, nor stay exactly the same size, and it does not melt at 900°F—the melting point for most structural steels is well above that (typically several hundred more degrees).