This paper describes the behavior of a cold-formed steel (CFS) framed structure in response to a real fire that occurred in a residential apartment. A set of residential buildings is composed by four identical four-story blocks of eight apartments per floor, housed by poor people; each apartment has 44 m² of total area. The Brazilian Code does not require that this type of building be checked for fire safety. A real fire in a residential apartment was modeled, as well the structural fire resistance; the maximum fire temperature reached during the burning on the structural material was assessed by scanning electron microscopy tests for the further comparative analysis between the theoretical and actual results. A CFD scenario representative of the actual building geometry, materials and fire behavior was modeled by means of the software SMARTFIRE. A steel thermal analysis in fire situation was conducted by means the software SUPERTEMPCALC, and the structural analysis of the steel frame was performed according to the expressions recommended by the Brazilian Standard for design of CFS for room temperature, based on the AISI/USA, but using the strength reduction factors recommended by Eurocode 3 part1.2.
Real fire; natural fire; small apartment; cold formed steel; thermal analysis
