Dynamic mechanical properties and energy dissipation analyses of cement-iron ore tailings foam composites with various fiber types and contents

The cement-iron ore tailings foam composite (CIFC) provides a sustainable solution by partially replacing cement with iron ore tailings. Fibers can be incorporated into composite materials to improve crack resistance and toughness, thereby enhancing dynamic mechanical performance. However, the dynamic properties of CIFC with fibers remain inadequately explored. This study investigates the dynamic compressive behavior of CIFC reinforced with glass fiber (GF), basalt fiber (BF), and polyvinyl alcohol fiber (PVAF) at contents ranging from 1.0 % to 2.5 % under varying strain rates. X-ray diffraction (XRD) indicates a higher content of hydration products in BF- and PVAF-reinforced CIFC than in the GF-reinforced composite. Scanning electron microscopy (SEM) reveals that a fiber content of 2.0 % optimizes fiber–matrix bonding and reduces interconnected pores and micro-cracks. Dynamic tests using a split Hopkinson pressure bar (SHPB) show that all specimens reach optimum performance at a fiber content of 2.0 % at strain rates of 120–250 s −1 . PVAF-reinforced CIFC exhibits superior structural integrity after impact, while GF-reinforced CIFC achieves higher dynamic mechanical performance. For instance, at 250 s −1 , GF2.0 attains a compressive strength of 18.21 MPa, compared to 14.49 MPa for BF2.0 and 13.24 MPa for PVAF2.0. Energy dissipation analysis further reveals the strong dependence of energy absorption on fiber type and content. Among all mixes, GF2.0 exhibits the greatest sensitivity to input energy, with its strain energy density (SED) increasing from 262.48 to 1300.29kJ/m 3 , energy dissipation ratio ( R ) from 2.14 % to 9.66 %, and dissipated energy density ( E V ) from 62.37 to 1231.02kJ/m 3 , respectively, as the input energy rises from 515.50 to 2229.30 J. These findings provide insights for designing impact-resistant structural applications using CIFC with optimized fiber parameters.