Performance of eco-friendly concrete made from recycled waste tire fine aggregate as a replacement for river sand

Abstract

Tires are non-biodegradable and can last long, providing an environmental risk. This material could substitute natural aggregate in concrete, reducing aggregate consumption, promoting sustainable development, and protecting the environment. This study examines the mechanical strength, shrinkage, durability, and structural performance of concrete prepared with varied content of waste tire fine aggregate (WTFA) up to 75 % as a substitute for sand at two water-to-cement ratios of 0.30 and 0.55. Results indicate that slump, dry density, and mechanical strength all decrease as WTFA content increases. At both w/c ratios, the compressive and splitting tensile strength decreases by up to 71–77 % and 59–62 %, respectively, when the WTFA content is 75 %. Young's modulus dropped by about 71–77 % when the WTFA content was 75. In contrast, the flexural load-carrying capacity declined by about 63–69 % for the beam with 75 % WTFA. The 100-day shrinkage test reveals no apparent shrinkage up to 20 % WFTA. However, the control specimens show the lowest shrinkage. Further, increased WTFA content increased the apparent porosity, water absorption, and chloride ion penetration. Nevertheless, the statistical analysis (ANOVA) revealed no significant effects on mechanical and durability properties due to incorporating WTFA in concrete. The outcome demonstrates that 20 % WTFA can be used as a replacement for river sand in many structural concrete whose design strength is not significantly high (fcat28days ≈ 20 MPa).