ABSTRACT

This study explores the effectiveness of using recycled irradiated waste polyethylene terephthalate (PET) as a partial replacement for cement in the formulation of cementitious grouts. This study investigates the impact of regular and irradiated PET and fly ash (FA) on the flowability, drying shrinkage, compressive strength and flexural strength of cementitious grouts. It was observed that partial replacement of cement with normal PET (in the range of 5–10% by mass of cement) resulted in a reduction (between 26% and 46%) in compressive strength of the cured grout. Interestingly, the use of irradiated PET instead of regular PET restores 8–22% of the compressive strength. Additionally, response surface methodology (RSM) is used to design the experiments, analyze the responses, and optimise the independent variables. A high R² and adequate precision of the ANOVA is an indication of a good agreement between the factors and responses. Besides, gamma irradiation makes it possible to use a higher percentage of 2.57–4.75% waste PET as cement replacement while retaining the target flow and strength properties. Therefore, the proposed treatment of PET with gamma radiation could be an effective way for recycling waste PET and a significant step towards achieving the zero-waste challenge.

摘要

本研究探讨了使用回收的辐照废聚对苯二甲酸乙二醇酯 (PET) 作为水泥浆配方中水泥的部分替代品的有效性。本研究调查了常规和辐照 PET 和粉煤灰 (FA) 对水泥灌浆的流动性、干燥收缩、抗压强度和抗弯强度的影响。据观察，用普通 PET（按水泥质量计在 5-10% 范围内）部分替代水泥会导致固化灌浆的抗压强度降低（26% 至 46%）。有趣的是，使用辐照 PET 代替常规 PET 可恢复 8-22% 的抗压强度。此外，响应面方法 (RSM) 用于设计实验、分析响应和优化自变量。高R²和足够的方差分析精度表明因素和响应之间的良好一致性。此外，伽马辐照可以使用更高百分比的 2.57-4.75% 废 PET 作为水泥替代品，同时保持目标流动和强度特性。因此，提出的用伽马辐射处理 PET 可能是回收废 PET 的有效方法，也是实现零废物挑战的重要一步。