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This study presents experimental and numerical investigations of simply supported steel reinforced concrete (RC) beams under fire. The temperature field of cross sections, the vertical deflection at mid-span, and specifically the axial expansion displacement at beam-ends were measured during the fire tests. A novel finite element (FE) model of a RC beam under fire was developed, in which the water loss in the heat transfer analysis and the concrete transient strain in the mechanical analysis were considered. Based on the validated FE model proposed in this study, parametric studies were conducted to investigate the effects of the beam type, the protective layer thickness, and the load ratio on the thermal and mechanical behavior of simply supported RC beams. It was found that greater fire resistance and fire performance of girder beams in comparison to secondary beams contributed to the non-structural reinforcements, which effectively compensated for the reduced tensile capacities of structural reinforcements because of the degradation of the material properties. In addition, the history of normal stress distributions of concrete under fire can be divided into three phases: expansion, stress redistribution and plateau phases. [ABSTRACT FROM AUTHOR]

Façades made of glass are viewed as one of the weakest parts of a building which can easily break in case of fire and change the compartment fire dynamic by creating a new opening for air to enter. A total of six clear glass panes were placed 750 and 500 mm away from a 500 × 500 mm n-heptane pool fire to investigate the breakage behavior of fully exposed framing glass façades. Both float and toughened glass panes with a dimension of 600 × 600 × 6 mm were tested. The results presented include the time to breakage occurrence, heat release rates, incident heat flux, central gas temperatures and glass surface temperatures. The crack initiation and propagation as well as the loss of integrity of the glazing assembly were also recorded. The experimental results established that the critical temperature difference and heat flux for float glass were approximately 90 °C and 14 kW/m. All their cracks were initiated from the edge of glass pane and intersected rapidly, forming some islands, but the fraction of fallout was considerably small because of the protection of frame. However, the toughened glass did not break even though the center temperature reached a high value of 413 °C. Using finite element method, breakage mechanism of float glass pane is demonstrated, and the numerical predictions are further compared with the experimental measurements. [ABSTRACT FROM AUTHOR]