Sustainable paving blocks by the combination of plastic waste and sand

Drinking water from plastic bottles offers convenience and perceived safety compared to tap water, resulting in widespread consumption and substantial plastic waste accumulation. An average individual consumes around 2.0 L of bottled water daily, significantly contributing to environmental plastic pollution. Addressing this issue, this research highlights and investigates an innovative solution by evaluating the potential of recycling plastic waste into paving blocks. Specifically, the study is based on the assumption that plastic materials commonly found in bottled water packaging, which are Polyethylene Terephthalate (PET) from bottles, Polypropylene (PP) from labels, and High-Density Polyethylene (HDPE) from bottle caps, can act as an effective binder to combine with sand without the use of cement to produce the paving blocks. The investigation assesses critical physical and mechanical properties of the developed paving blocks, including apparent density, porosity, water absorption, and compressive strength, across varying proportions of plastic waste ranging from 30% to 70% by weight. The key results indicate that PET, PP, and HDPE waste can be effectively used to produce paving blocks with compressive strengths ranging from 14.57 to 22.03 MPa, with water absorption below 15%. The study identifies an optimal plastic content between 50% and 60% by weight, yielding paving blocks with satisfactory strength and durability. This research underscores a sustainable and practical approach to mitigating plastic waste, contributing valuable insights toward circular economic initiatives and environmental sustainability.