Optimalisasi Proporsi Limbah Plastik Campuran Terhadap Kuat Tekan Paving Block

Abstract

This study aims to analyze the effect of using Polyethylene Terephthalate (PET) plastic waste as a partial substitute for fine aggregate on the compressive strength of paving blocks and to determine the optimum proportion that can improve their quality. The research was conducted experimentally at the Civil Engineering Laboratory of Bina Darma University, Palembang, using triangular paving blocks measuring 30 × 30 × 30 cm with a thickness of 10 cm. The PET plastic waste replacement levels were 0%, 1%, 1.5%, and 2% by weight of fine aggregate. Compressive strength tests were carried out at the ages of 7, 14, and 28 days in accordance with SNI 03-0691-1996. The results showed that the addition of PET plastic waste increased the compressive strength compared to normal paving blocks. At the age of 28 days, the average compressive strength of the normal paving block was 10.77 MPa, while the paving blocks containing 1%, 1.5%, and 2% PET achieved compressive strengths of 11.93 MPa, 12.75 MPa, and 13.25 MPa, respectively. The highest compressive strength was obtained with the 2% PET mixture, reaching 13.25 MPa. Furthermore, the material testing results indicated that both the fine aggregate and PET plastic waste met the requirements for use as paving block constituent materials. Although the compressive strength increased, none of the mixtures reached the target design strength of f'c 40 MPa. Based on the findings, it can be concluded that the use of PET plastic waste as a partial substitute for fine aggregate has a positive effect on improving the compressive strength of paving blocks. The optimum proportion was achieved with the 2% PET mixture, indicating its potential application as Grade C paving blocks for pedestrian areas while supporting environmentally friendly plastic waste utilization.