Measurement of Thermal Properties of Building Materials

Abstract

This study is concerned with the measurement of the thermal properties of building materials,namely, the thermal diffusivity by the Periodic Stationary Method.

Two tests for measuring the thermal diffusivity of the concrete materials by the PeriodicStationary Method were made by considering two thicknesses : 1.5 and 2.0 cm. In each case, thethermal diffusivity was estimated based on amplitude ratio and phase change. Determination wasmade graphically by using the recorded thermograms and, theoretically, based on the resulting sinewaves. It was found that for 1.5 cm thickness the thermal diffusivity derived from the amplituderatio was 1.5695±0.1834x10-6m2.s-1and that obtained from the phase change was4.3953±0.1119x10-7m2.s-1. For the sample of 2.0 cm thickness, the corresponding thermaldiffusivities were 1.0687±0.1667x10-6m2.s-1 and 5.0304±1.0120x10-7m2.s-1 respectively.Based on the thermal sine waves obtained by graph plotting reveals that the 1.5 cm thicknessmaterial has thermal diffusivity measured by the amplitude ratio and the phase change of1.3953±0.0381x10-6m2.s-1 and 5.2931±0.3569x10-7m2.s-1 respectively. Two centimeterthick materials has thermal diffusivity of 1.1860±0.0667x10-6m2.s-1 and 6.0586±1.2999x10-7m2.s-1. After comparing with the reference value, the difference is minimal, especially whenthermal diffusivity was estimated based on phase change.