The effect of shredded plastic waste PET and HDPE substitution on concrete characteristics

The incompetence of recycling schemes has gradually led to alternative ideas to tackle the problem of plastic waste. This research was conducted from the context of environmental and development issues that are growing in Indonesia. This research focuses on how to apply plastic waste into concrete mixtures. PET (Poly-Ethylene Terephthalate) and HDPE (High-Density Polyethylene) plastic waste is shredded into 10-25 mm sizes and substituted as much as 5%, 10%, 15%, and 20% replacing fine aggregate to improve concrete characteristics. The results showed that the PET substitution of 5%, 10%, and 15%, the compressive strength still met the compressive strength plan ( f’c = 25 MPa). Whereas in the HDPE substitution variation, it is only the strength of the variation of 5% and 10% that still meets the compressive strength plan. In the split tensile strength test, there was a decrease in the strength of PET substitution with increasing percentage levels, while in HDPE substitution there was an increase in strength at levels of 5% and 10%. Overall, it was concluded that HDPE and PET shredding in concrete have an opportunity to help to reduce the build-up of plastic waste.