Effect of layered polyethylene terephthalate (Geopet) for reinforcing stabilized sand with fly ash

Abstract

Purpose This study aims to examine the reuse of plastic and fly ash (FA) to improve the soil and achieve sustainable development goals. Design/methodology/approach Sand from the Anzali port was reinforced with Geopet (GP) and stabilized with FA plus 3% sodium hydroxide. The GP was placed in FA-stabilized soil and the California bearing ratio (CBR), and unconfined compressive strength (UCS) tests were performed on samples at the optimum moisture content. Findings The results showed that the improvement in the optimum CBR was 174.9%. The UCS increased 15.25% and 48.65% in soil reinforced with three layers of GP plus 15% FA over those containing 10% and 5% FA, respectively. Additionally, the current analysis used response surface methodology (RSM) to investigate the impact of FA percentage, GP layers and their interaction on CBR. The results highlight the efficacy of the used RSM model, as evidenced by the significantly low p-value (<0.0001). Originality/value This demonstrates the suitability and effectiveness of RSM for evaluating CBR in this scientific study.