Mechanical properties of ambient cured fly ash‐slag‐based engineered geopolymer composites with different types of fibers

Abstract In this paper, low‐strength polyvinyl alcohol (L‐PVA) fibers, high‐strength polyvinyl alcohol (H‐PVA) fibers, and polyethylene (PE) fibers were used to prepare ambient cured fly ash‐slag‐based engineered geopolymer composites (EGC). The effects of fiber types and fiber volume fractions (1.5%, 1.75%, 2.0%, 2.25%, and 2.5%) on the compressive strength and tensile performance of EGC were evaluated. It was found that by increasing the fiber volume fraction from 1.5% to 2.5%, L‐PVA fibers had the lowest influence, whereas PE fibers had the highest influence on the compressive strength of EGC. The optimum fiber volume fractions of L‐PVA, H‐PVA, and PE fibers were 1.75%, 2.25%, and 1.5%, respectively, for EGC to achieve the best tensile performance. Scanning electron microscope (SEM) investigations showed that the bonding performance of PE fibers to the EGC matrix was higher than those of L‐PVA and H‐PVA fibers to the EGC matrix.