Mechanical, physical and durability evaluation of soil-cement blocks incorporating polyethylene terephthalate (PET) waste

Purpose This study aims to evaluate the influence of different proportions of polyethylene terephthalate (PET) waste (0.5%, 1.0%, 1.5%) on the physical, mechanical and durability properties of soil-cement blocks. Design/methodology/approach The compressive strength, water absorption, mass loss and ultrasonic pulse velocity (UPV) of blocks containing PET waste were evaluated. Additionally, scanning electron microscopy (SEM) was used to analyze the morphology of PET and its interaction with the cement matrix. Findings The results demonstrated an improvement in the compressive strength of up to 13.39% for blocks with 1.0% PET and 13.11% for blocks with 1.5% PET at 28 days. Water absorption and mass loss significantly decreased with higher PET content (1.0% and 1.5%). However, the UPV was reduced, indicating the presence of internal discontinuities in the material due to the incorporation of PET waste. Originality/value The study highlights the potential use of PET waste as an additive in soil-cement blocks, suggesting that although the incorporation of PET improves durability and strength, it may create discontinuities in the material. It is proposed that the optimization of PET content could achieve a balance between enhancing durability and maintaining the structural integrity of the material.