EVALUATION OF THE THERMAL PROPERTIES OF CONCRETE AND SOME TECHNIQUES FOR THEIR IMPROVEMENT

This paper reports the results of experiments conducted to evaluate moist thermal diffusivity, thermal conductivity and specific heat of most concrete. Since thermal diffusivity was recognized to be a representative material property, diffusivity was investigated considering the influence of mix proportions. In addition a theoretical estimate of the diffusivity of concrete as a composite material was made. Calculation of the diffusivity of fine and coarse aggregate and the study of the relation between diffusivity of aggregate and rock type were also investigated. Several methods were examined to improve thermal diffusivity of concrete. Effective methods investigated were to use aggregate of rock type having high diffusivity and to increase the aggregate content and water cement ratio. Furthermore, it was found that the use of a superplasticizer was very successful in improving thermal diffusivity. (Author/TRRL)