Effect of Different Sand Types and Fractions on Ballistic Resistance of High-Performance Steel Fibre-Reinforced Concrete

High-Performance Fibre-Reinforced Concrete (HPFRC) is an advanced composite material known for its exceptional energy absorption and dissipation capabilities. To improve its ballistic resistance, HPFRC samples were prepared using 1.5% steel fibre content and varying levels of silica. Ballistic trials employed standard 7.62 × 39 cartridges, each comprising a full metal casing around a mild steel core. Resulting damage and failure mechanisms were mapped using a 3D photogrammetry system. Six different concrete mixtures were tested, each incorporating aggregate fractions of 0/2 mm along with three types of micro sand, the largest of which measured up to 1.2 mm in grain size. The results suggested that increasing the proportion of 0/2 mm silica sand was relatively minor.