Abstract:
Optimizing energy consumption is one of the building designers concerns. This explains
the technology assessment and development of new building materials. Among these
materials lightweight concrete, which can be play a role as an insulator, while maintaining
adequate levels of performance.
The knowledge of the materials thermal properties used for building shielding such as
thermal conductivity, thermal resistance and heat mass are the most important features for
the choice of a thermal insulation material
This work is a contribution to the study of cork lightweight and polystyrene lightweight
concretes thermal behaviour. These materials are intended to be used for roof insulation
and other building components and there lightness makes them an interesting technical
solution for the building tower.
Regarding the experimental measurements, in steady regime for the thermal conductivity,
we have used the “Boxes method”. Thermal resistance and mass heat are obtained by
calculation.
The experimental results made it possible to specify the effect of the water content, the
materials density and the fibres dosage on the materials thermophysical properties.
The mathematical modelling of coupled heat and mass transfer occurring within building
walls is obtained with using Luikov's model. The differential equations obtained are
discredited by the finite element method.
The obtained results illustrate the temporal evolutions of the temperature and the moisture
content, and the distributions of the temperature and moisture content inside the wall for
several periods of time. They allow us to specify the effect of the nature and fibre dosage
on the heat and mass transfer.
