Development of a thermal insulating polystyrene concrete block

Abstract

Polystyrene concrete was considered as a new invention in construction industry as the development is still not matured. Polystyrene is a good lightweight material that is used to replace aggregate in concrete because it has good heat insulation while providing sufficient strength. There were four mix designs proportions in this research by using different percentages of polystyrene to replace aggregate: 0 %, 25 %, 50 % and 100 %. The concrete with 0 % polystyrene replacement acts as a control mix. The mass and density of polystyrene concrete were compared with normal concrete. The water absorption of polystyrene concrete was measured to know the void ratio of the concrete. The compressive strength was determined by using GoTech Universal Testing Machine and rebound hammer to compare the result. The average compressive strength at 28 days for 100 % polystyrene concrete was around 7.64 MPa with mass of only 3.37 kg. The density of the concrete was less than 1000 kg/m3. The thermal insulation of polystyrene concrete was about 84 % better than normal concrete. The best design for this research is the concrete with 50 % aggregate replacement by polystyrene as it achieved compressive strength of 22 MPa with lightweight properties. As a conclusion, polystyrene concrete with 100 % aggregate replacement at this stage is only suitable to be used for non structural components due to its low strength. To produce a more satisfying result, superplasticizer can be added to avoid segregation in the concrete mixture.