Fire resistance of steel beams with integrated fire-resistant and decorative constructions

This paper investigates the fire resistance of steel beams with integrated fire-resistant and decorative constructions. Four novel forms of fire protection constructions that simultaneously meet the requirements of fire protection and decorative performance in steel residential housing are first devised. Five simply supported H-shaped steel beams encased by such constructions are tested in a fire test furnace to reveal the variation of their temperature fields and mechanical properties under the ISO-834 standard heating condition. A series of test phenomena, temperature-time and displacement-time curves are obtained from the tests. Corresponding results show that the specimens are far from reaching their ultimate limit state, which validates the effectiveness of the proposed constructions in fire protection. Additionally, the influence on the fire resistance caused by the variation of the construction components is determined by comparing the temperatures and displacements of all the specimens. Finally, a finite element model corresponding to the specimens is established in the FE software package ABAQUS. The heat transfer and thermal-mechanical coupling analyses are conducted in succession, and the model is verified compared with the experiment results. Then a preliminary parametric study is carried out, revealing that the thickness and thermal conductivity of non-intumescent fire-retardant coating and the thickness of autoclaved aerated concrete blocks may affect the fire resistance of the encased steel beams perceptibly.