At what temperature do cold-drawn steel cables fail in a fire?

At what temperature do cold-drawn steel cables fail in a fire?

• A. 600 Degrees F
• B. 1000 Degrees F
• C. 800 Degrees F
• D. 1200 Degrees F

Answer: (C)

Cold-drawn steel cables are high-tension, but heating in a fire rapidly reduces their strength and stiffness. By around 800°F, the steel loses enough yield strength that it can no longer carry the design tension, causing failure even under the same load. Cold-working increases strength but reduces ductility, making these cables more susceptible to strength loss at lower temperatures than some other steels. So, at about 800°F the cables are expected to fail in a fire, whereas higher temperatures like 1000°F or 1200°F would also cause failure if exposure continues, the commonly cited threshold for these cables is 800°F. Actual failure depends on exposure time, protection, and how much load is being carried.

Cold-drawn steel cables are high-tension, but heating in a fire rapidly reduces their strength and stiffness. By around 800°F, the steel loses enough yield strength that it can no longer carry the design tension, causing failure even under the same load. Cold-working increases strength but reduces ductility, making these cables more susceptible to strength loss at lower temperatures than some other steels. So, at about 800°F the cables are expected to fail in a fire, whereas higher temperatures like 1000°F or 1200°F would also cause failure if exposure continues, the commonly cited threshold for these cables is 800°F. Actual failure depends on exposure time, protection, and how much load is being carried.