Mechanical Properties of Eco-friendly Alkali-activated Concrete Containing Plastic Waste and Crumb Rubber Tires
Abstract
This study aims to investigate an eco-friendly concrete for sustainable development in construction materials. Alkali-activated concrete was produced using by-product wastes, i.e., fly ash and rice husk ash. Crumb rubber obtained from waste tires was used as fine aggregate. Crushed plastic automotive parts were used to replace natural limestone at replacement levels of 10% and 20% by volume. The results showed that adding crumb rubber and plastic waste up to 20% reduced the unit weight and slump of alkali-activated concrete, while increasing its strain capacity under compression. The 28-day compressive strength of rubberized concrete containing plastic waste ranged between 5.4 and 10.0 MPa, suggesting its suitability for use as a subbase beneath slabs or pavements. In addition, based on the mechanical performance, environmental sustainability, and cost-efficiency discussed in this study, incorporating 10% crumb rubber or 10% plastic waste is considered the optimal replacement level in concrete mixtures.