Thermal analysis of steel and concrete composite beams cross sections in fire situations

Abstract

The fire poses a considerable risk to human safety and, therefore, fire protection is a solution that should be incorporated into the construction system of a building. Composite beams, when subjected to fire, lose strength and stiffness due to the degradation of the mechanical properties of their materials. This paper aims to perform the thermal analysis of steel and concrete composite beams in fire situation. The software ABAQUS Version 6.14 [1] was used to develop numerical methods, whose results were analyzed and compared with the values obtained by the simplified calculation method prescribed in ABNT NBR 14323:2013 [2]. Thereby, the thermal behavior of the composite cross-section and the influence of the material and the type of fire protection were analyzed. The results showed that, for a certain type of protection and size of the metallic profile, the temperatures given by the Brazilian Standard may differ substantially from those obtained by numerical simulation.