Compressive strength, sound absorption coefficient (SAC) and water absorption analysis of HDPE plastic waste reinforced polystyrene and Portland cement for lightweight concrete (LWC)

Abstract

This project research presents compressive strength, sound absorption coefficient (SAC) and water absorption analysis of High-Density Polyethylene (HDPE) plastic waste reinforced polystyrene and Portland cement for lightweight concrete (LWC). The research is aimed into the issue of waste materials such as HDPE plastic waste and polystyrene waste into lightweight concrete (LWC) application. Modifications with waste material may improve the qualities of lightweight concrete (LWC), and HDPE plastic waste may serve as a partial substitute for natural aggregates, which are rapidly depleting. It has been proposed that HDPE plastic waste and polystyrene be used as an alternative aggregate material to reduce environmental impact. In this study, four composition ratio of HDPE plastic waste reinforced polystyrene and Portland cement to produce LWC; which are (a) 0.5 HDPE plastic waste : 1.0 polystyrene: 1.0 Portland cement, (b) 1.0 HDPE plastic waste : 1.0 polystyrene : 1.0 Portland cement, (c) 1.5 HDPE plastic waste : 1.0 polystyrene : 1.0 Portland cement, and (d) 2.0 HDPE plastic waste : 1.0 polystyrene : 1.0 Portland cement. The highest rate of compressive strength attained was 97.28 kN with the composition ratio of 1.5 HDPE plastic waste: 1.0 polystyrene : 1.0 Portland cement. It was discovered that a larger proportion of plastic lowered the strength of concrete. On the other hand, the optimum composition ratio of HDPE plastic waste reinforced concrete for lightweight concrete (LWC) produces the appropriate strength for LWC when the composition ratio is optimized. For sound absorption analysis, the higher coefficient is 0.42 SAC at 350 Hz to 1500 Hz for the composition ratio of 1.5 HDPE plastic waste : 1.0 polystyrene : 1.0 Portland cement. Water absorption characteristics of HDPE plastic waste and polystyrene for LWC dropped with increasing plastic waste content up to 0.50%.