One of the many roles of forensic engineering services people may not be aware of is assessing steel framing following a fire in a building. Steel can withstand high temperatures, and sometimes it may even look like it was unaffected after a fire. However, even if it appears to be normal, the integrity of the steel could have been compromised. A structural forensic engineer looks at many different factors to determine the integrity and viability of steel framing following a fire. Here are some of those factors, along with some background on how fire affects steel.

How A Fire’s Temperature Impacts Steel Strength

The higher a fire’s temperature is, the more steel will be impacted. The framing could buckle and twist, as well as experience a reduction in stiffness and overall yield strength. But the unique thing about steel is it’s possible for it to regain all its properties back if the fire’s temperature does not exceed 1,300 degrees Fahrenheit for more than about 20 minutes. However, if the temperature is higher than that or it takes longer for the fire to be extinguished, then a structural forensic engineer will likely find some major issues with the integrity of the steel.

Determining Whether Steel is Usable After A Fire

If you happen to watch steel framing as a fire is taking place, the average person will deem it unusable. However, buckling and other deformations can occur in steel at relatively low temperatures. This does not mean the overall integrity of the steel framing is completely and permanently compromised, though. Each situation is unique, which is why forensic engineering practices are needed to determine exactly whether steel framing is strong enough for people to even walk into, much less use the building ever again.

How Forensic Engineers Assess Steel Framing

A structural forensic engineer will look at the external appearance of steel to determine how high the temperature of a fire got, and how long it remained at that temperature. If the steel looks a normal color and there are no other obvious deformities, then most likely the temperature was less than 1,300 degrees Fahrenheit. But if the temperature exceeded that number, then the surface of the steel may appear oxidized, show signs of pitting, reduction of thickness and will have a different color. Once the structural forensic engineer determines the severity of the impact the fire had on the steel framing, he can determine whether the steel is usable as it is, if it can be used with slight modifications or if a complete replacement is needed.

BE Structural has a solid team of experts to provide many different forensic engineering services. A fire can cause an extensive amount of damage in a short period of time, so it’s important to have a structural engineer analyze the damage to deem the building safe or unsafe. To learn more about how the process works, feel free to contact us at any time.