Fire Resistance of Fly Ash Blended Lightweigth Concrete

An experimental study was carried out to examine eight mixtures made with pumice powder and fly ash in order to produce lightweight materials. Additionally, textile fiber was utilized to increase strength of the lightweight concrete. It was found that 28 days compressive strength, thermal conductivity, sound transmission speed, water absorption and unit weight varied from13.0 to 20.9 MPa, 0.34 to 0.43 W/mK, 2.52 to 3.11 km/s, 14.3 to 17.5 % and 1.19 to 1.40 g/cm3, respectively. It was seen form SEM pictures of samples that reaction products of cement were formed. In all samples, there was no deformation due to temperature from 300 to 700°C. However, at 900°C, all samples were deformed and showed cracks of 3 mm. The compressive strengths of cracks samples were obtained from 8.1 to 10.2 MPa. The results showed that pumice and fly ash decreased thermal conductivity and sound transmission. Also, samples were not decomposed at high temperature when pumice and fly ash used as admixtures in lightweight concrete.