Several types of fire resistive materials have been supplied by manufacturers for this study. In this paper, detailed results will be presented for three materials, all spray-applied FRMs, one based on a gypsum binder with a lightweight filler and two based on a portland cement-based binder with mineral fibers. The samples evaluated in the slug calorimeter were of size 152.4 mm x 152.4 mm x 25.4 mm. Heat capacities, densities, and thermal conductivities of these materials had been previously determined by two laboratories (2, 3). One of the testing laboratories reported their results for thermal conductivity to have an uncertainty of ± 3 % (2). The experimental and computer model values determined in this study will be compared to these testing laboratory-determined values. The two fiber/portland cement-based materials, here designated as FRM A and FRM B, had room temperature densities of 314 kg/m3 and 237 kg/m3, respectively. For the gypsum-based FRM, designated here as FRM C, the density was 293 kg/m3. More details on the materials and their properties can be found in Reference (1). Representative optical microscopy images for the three materials are provided in Figure 1.
Figure 1 Optical microscopy images of the three FRMs: left- FRM A with top scale bar on right side of image indicating a dimension of 1.25 mm, center- FRM B with top scale bar on right side of image indicating a dimension of 1.5 mm, and right- FRM C with top scale bar indicating a dimension of 0.5 mm, from ref. (1).