Toughening characteristics of polypropylene fiber modified alkali-activated slag stabilized aeolian sand

The progressive exhaustion of natural river sand reserves coupled with escalating global construction demands has positioned aeolian sand as an increasingly material in sustainable infrastructure development, particularly given current environmental resource constraints. In this study, polypropylene fiber (PPF) was used to modify alkali-activated slag-stabilized aeolian sand. A series of tests, including unconfined compressive strength (UCS), digital image correlation (DIC), and scanning electron microscopy (SEM), were conducted to evaluate the mechanical performance and failure mechanisms of the modified material. The results indicate that incorporating 9 mm PPF at a dosage of 0.24% significantly improves compressive strength. The fibers form a three-dimensional skeleton structure, which helps disperse external loads, enhances lateral deformation capacity, and improves ductility. Compared to unreinforced specimens, PPF-reinforced specimens exhibit greater load-bearing capacity and energy dissipation efficiency. This research provides a theoretical and technical reference for the high-value utilization of aeolian sand in subgrade construction.