Structural lightweight concrete (LWC) has recently acquired research importance because of its good thermal insulation properties. However, there is a lack of knowledge about its thermal properties at elevated temperatures. The thermal properties, such as thermal conductivity and specific heat, of porous LWC vary depending on the aggregates, air voids, and moisture content of the LWC in question. To study these effects, in this paper, we measured the thermal properties of three types of structural LWCs at different temperatures, combining different characterization techniques, namely, differential scanning calorimetry (DSC), laser flash analysis (LFA), and modified transient plane source (MTPS). Bulk density and porosity were also evaluated. Specific heat is analyzed by the DSC technique from 20 to 1000 °C and the MTPS technique from 20 to 160 °C. Thermal conductivity is studied using MTPS and LFA techniques at temperatures ranging from 20 to 160 °C and 100 to 300 °C, respectively. The results indicate that the thermal properties of LWC are highly affected by moisture content, temperature, and porosity. For LWC, the current Eurocodes 2 and 4 assume a constant value of specific heat (840 J/kg°C). This research reveals variability in temperatures near 150, 450, and 850 °C due to endothermic reactions. Furthermore, for low temperatures, the higher the porosity, the higher the thermal conductivity, while, at high temperatures, the higher the porosity, the lower the thermal conductivity. Thus, Eurocodes 2 and 4 should be updated accordingly. This research contributes to a deeper understanding and more accurate prediction of LWC’s effects on thermal properties at elevated temperatures.

Gypsum plasterboards are widely used for compartmentation and for retarding the spread of fire in buildings. Although numerous heat transfer studies have been conducted, literature indicates there are extensive differences in the thermal properties used in these studies. Comprehensive experimental and numerical analyses have been conducted to elucidate the leading factor in the ablation of a gypsum board system when it is exposed to the standard fire resistance test. A methodology based on both simultaneous thermal analysis and computational modelling is proposed to understand the behaviour of a gypsum plasterboard when the boundary temperature increases quickly as one side of the wall is subjected to the standard ISO 834. Finally, four different wall assemblies made of a commercial fireproof plasterboard system are exposed to the standard test. The temperature on the unexposed face is examined to validate the computational model of the plasterboard. Copyright © 2015 John Wiley & Sons, Ltd.