Strength and insulating properties of building blocks made from waste materials

This paper presents the results of an investigation to study the possibility of developing concrete blocks using waste materials. The blocks were produced from three waste materials: vermiculite and polystyrene beads, which were used as lightweight aggregates with different proportions in the mix, and cement kiln dust (CKD), which was used as a partial replacement for cement. The strength of the three types of blocks and the strength of masonry columns constructed from the blocks were compared with another two types of normal weight concrete blocks with and without high thermal insulation properties. The thermal insulation property of the developed lightweight concrete blocks was also compared. Results showed that lightweight concrete blocks manufactured from polystyrene had lower thermal conductivity than vermiculite and ordinary concrete blocks despite the variation in the density and compressive strength, and that the addition of up to 15% CKD as a cement replacement has a negligible effect on the strength of the block.