Home flèche Bulletin flèche Burned steel

Burned steel

Tuesday September 4, 2018

Burned steel From ore smelting up to welds done on a construction site, steel manufacture requires heat throughout the process. But once in a structural application, what happens to the steel when it is exposed to the heat of a fire?

When the steel is exposed to heat for a sufficient period of time, it can reach a temperature where changes occur in its metallurgical composition: these permanently alter its characteristics and the steel no longer has the properties to fulfill its structural role in accordance with the codes and standards.


 However, this temperature does not need to be reached for damage to occur. Indeed, long before it is, the strength of steel as well as its rigidity will have already been very strongly reached. It is this rapid and significant alteration of the structural characteristics of steel in the presence of heat that makes it a poor material for fire resistance because, when exposed to heat, it is not able to fill its role and easily undergoes permanent deformations.


In addition, when subjected to heat, the steel expands significantly. This dilation can lead to undesirable efforts or movements to the structure. In the case of large buildings, this can cause damage to the structure as well as architectural elements attached to the structure, even far away from the fire, in places with little to no heat. This expansion can also cause steel damage by exposing it to non-uniform temperature gradients during a fire, which can be sudden, especially when firefighters try to extinguish the fire with cold water


You are wondering if you can reuse a structure exposed to heat? Do not hesitate to contact the EMS Investigation team to have the right information about the damage it has suffered and to obtain the best way to intervene, considering all the elements specific to your situation.



PDF version



About the Author

Nicolas Larouche finished his engineering degree in December 1999 and worked as a structural engineer in the early years of his career. Since 2007, he has devoted himself almost exclusively to the expertise of damaged structures and building envelopes. In addition to carrying out numerous investigations, he leads the Investigation EMS team that is dedicated to providing a service that exceeds the expectations of the industry, based on objectivity, rigour, transparency, honesty and above all PASSION. He has also been recognized as an expert witness by the courts on several occasions.

Do you like this Bullletin?

Back to bulletins list