Experimental and theoretical investigations on thermophysical properties of concrete produced from different aggregates

In this study, experimental and theoretical investigations are performed for obtaining new concrete types with relatively high strength, low density and good thermal properties for energy efficient buildings. For this purpose, different types of concrete samples were prepared with a constant water-cement ratio, and normal aggregates replaced by pumice, expanded perlite and rubber aggregates at different volume fractions such as 10%, 20%, 30%, 40% and 50% of the total aggregate volume. In totally, 108 samples with different materials and their compositions were produced. Compressive strength tests were all conducted and the hot disk method was used to establish thermal property values of concrete samples. In order to determine the most suitable concrete samples, heat flows through the produced and commonly used concrete samples are calculated using a program developed in MATLAB. Calculation method for the heat flow is based on solution of transient heat transfer problem for the multilayer structures. The program is executed to calculate hourly heat gain values for these samples over a period of 24 h during design day for Gaziantep, Turkey. The results showed that the maximum reduction in heat gain values are obtained for EPC50 wall with thicknesses between 10 cm and 30 cm, which are 46.14 and 71.15 percent, corresponding to conventional concrete, respectively. Keywords: Concrete, pumice, perlite, rubber, heat gain, energy efficient building