Experimental study on the surface light and thermal properties of bamboo

Abstract

The surface light and thermal properties of bamboo are important for its application in building envelope. To obtain systematically these properties parameters and clarify the potential impact factors, spectral reflectivity (ρ) and hemisphere emissivity (ε) tests are carried out on six typical bamboo products, and the impacts of bamboo-based panel process, moisture content and varnish coating are investigated. The tests provide a valuation range of reflectivity and emissivity for each kind of bamboo. The factors impact analyses quantitatively show the properties change of different bamboo-based panels compared with the raw bamboo. In general, the ρ and ε of the moist specimen groups show a downward trend compared with the dry groups, but no clear correlation is found between the properties parameters and the gaseous moisture content. The surface varnish coating causes significantly decrease of ρv and ρe, but slight increase of ρuv and ε to the raw bamboo. A similarity factor, f2, of the integration curves for calculating ρ and ε is introduced as an indicator to characterize the homogeneity of bamboo, showing that both raw bamboo and bamboo-based panels have inhomogeneity in varying degree.