Hygrothermal properties of lightweight concrete: Experiments and numerical fitting study

This paper presents an experimental research work in order to obtain the main hygrothermal properties of different mixes of lightweight concrete (LWC) produced from expanded clay. Nowadays, the current state of art assumes an exponential relationship between the moisture content and the thermal properties for this kind of building material. The prime novelty of this study is the experimental determination of the actual hygrothermal properties for different LWC mixes with material densities ranging from 900 to 1400 kg/m3, as well as the least squares best-fitting curves in order to obtain accurate mathematical expressions that permit us to optimize the hygrothermal behavior of new construction products made up of LWC. In this way, the experimental data set is compared with those for the Standard and a new analytical solution is obtained, giving place to a new analytical solution taking into account the relationship among the heat, moisture and density. Finally, the results and conclusions reached in this work are exposed.