The innovative Fiber reinforced geopolymer fly ash-based geopolymer in loose sand stabilization

Abstract

Geopolymer (GP) has recently emerged as a new and environmentally friendly alternative to standard soil stabilization agents such as lime and Ordinary Portland Cement (OPC) to reduce environmental concerns. The addition of fibers to treated soil limits crack propagation, enhancing its strength even further. This study used high calcium class C fly ash (CFA) reacted with 10 M NaOH as a geopolymer (GP) binder to treat weak sand soil. Polypropylene (PP) fibers with a length of 4.5 mm were used as reinforcement in amounts ranging from 0.3 to 1.5%. Microstructure and unconfined compressive strength (UCS) testing were performed on the generated specimens. The study proved the benefits of fiber inclusion in improving the mechanical behavior of the treated weak soil. Superior strength characteristics were observed in GP- treated soil mixes with a binder content of 20% and an Activator/Binder (A/B) ratio of 0.4 reinforced with 1.5% PP fibers by weight, indicating that they can be used as a sustainable alternative to traditional binders in deep soil mixing applications.