Progrès de la recherche en sciences appliquées Libre accès

Abstrait

Effect of additives on mechanical and thermal properties of lightweight foamed concrete

Hanizam Awang; Md Azree Othuman Mydin and Ahmad Farhan Roslan

This paper reports the results of experimental works that have been performed to investigate the mechanical and thermal properties of lightweight foamed concrete (LFC) with different additives. LFC with three different densities of 600, 1000 and 1400 kg/m3 were cast and tested. Fly ash, lime and polypropylene fiber were incorporated with the LFC at different proportions. Compressive, flexural and drying shrinkage tests were carried out up to 180 days to evaluate the mechanical properties. The Hot Disk Thermal Constants Analyzer was used to establish different thermal conductivity values of LFC of different densities and additives. Scanning electron microscopy was used to give a detail view on each of particles produced by the reaction of additives in hydration process. The addition of additives in LFC showed no contribution on compressive strength but improvement in the flexural and shrinkage test results. LFC integrating various additives only contribute slight increase for thermal properties. Experimental results show that lower density LFC translates to lower thermal conductivity. The density of LFC is controlled by the porosity where lower density LFC signifies greater porosity hence thermal conductivity changes notably with the porosity of LFC because air is the poorest conductor compared to solid and liquid due to its molecular structure