Teses #estruturas externas

Steelworks outside a building in fire situation are exposed to radiation that come from the windows in the façade and from flames, as well as the convection of hot gases. The absorption of the heat for the element depends on its placement in relation to the openings. Margaret Law, based on many experimental data about fire in buildings, estimated the external heat transfer to steel elements and the maximum temperature value reached by them. The Eurocode 1, part 1.2 (2002) and Eurocode 3, part 1.2 (2003) have adopted the method previously mentioned with small modifications. The Brazilian standard ABNT NBR 14323:1999 - “Dimensionamento de estruturas de aço de edifícios em situação de incêndio – Procedimento” (Steel structures fire design – Procedure) allows employment proposed by Eurocodes 1 and 3 without detailing it. A software, ExteelFire, to determine the maximum temperature on external steel structures of buildings in fire, based on Margaret Law’s method was elaborated in this work. Results from ExteelFire and the values determined by numerical analysis, with software CFD (CFD - Computational Fluid Dynamics) Smartfire and Super Tempcalc (thermal analysis) have been compared. Furthermore, results from ExteelFire and values determined in tests in fire compartment, in natural scale (Dalmarnock experiment and Mittal Steel Ostrava experiment) have also been contrasted. In this work it was also applied ExteelFire to commonly used situations in civil construction, showing conditions where the thermal protection can be excluded.