Numerical analysis of composite steel and concrete beams subjected to fire under different support conditions

Abstract

To evaluate the behavior of semi-continuous composite beams in fire, six finite elements numerical models with several steel profiles and slab dimensions were developed in ABAQUS software. The models took into account several behaviors usually suppressed in simplified analyzes such as: geometric and materials non-linearity properties and thermal expansion effects, including indirect stresses. Three support conditions were analyzed: simply supported (axial released), axial restrained and semi-continuous, totaling 18 analyzes. The different support conditions results were compared to each other and to the fire resistance time designed by simplified methods, which followed design code recommendations.

Effect of axial and rotational restraint on performance of composite beams with fire protection coating

“…The behavior of axially restricted beams was studied by Allam et al (2019) using computational methods, to investigate how the surrounding structures affect the survival of steel framed structures in fire. Other work included numerical studies of composite steel and concrete beams subjected to fire under different support conditions (Romagnoli and Silva, 2020). In this work, the authors compared the results found with the simplified design methods recommended by the main codes on steel structures in fire situations.…”