Study on the mechanical properties of non-calcined coal gangue geopolymer concrete reinforced by basalt fibers

Abstract Fiber-reinforced non-calcined coal gangue-based polymer concrete (BFCGGC) was synthesized utilizing gangue, slag, an alkali exciter solution, and coarse and fine aggregates, alongside basalt fibers as primary constituents. Mechanical characteristics of BFCGGC were investigated by varying the mass fractions of basalt fibers, while its micro-mechanism was examined using scanning electron microscopy. The findings indicated a trend in the compressive strength of BFCGGC, initially ascending and subsequently descending with fiber incorporation. Nevertheless, both tensile and flexural strengths exhibited continuous augmentation with the inclusion of fibers. Notably, basalt fibers demonstrated a pronounced improvement in the split tensile strength of BFCGGC, with a peak enhancement rate reaching 41.3%.