Akademik Veri Yönetim Sistemi
POWDER TECHNOLOGY, cilt.470, 2026 (SCI-Expanded, Scopus)
As mining operations extend deeper underground, the extraction of mineral resources faces increasingly extreme conditions. The immense in-situ stresses, violent rock bursts triggered by excavation, and intricate groundwater systems at such depths place unprecedented demands on strength and durability of shotcrete used for primary roadway support. This study investigates silica fume (SF) hybrid fiber-reinforced shotcrete (SFHF-S), focusing on joint effects of polypropylene fiber (PPF), SF, and steel fiber (STF) on its characteristic behavior after 14 days of curing. Strength, energy dissipation, damage evolution, and microstructural features of SFHF-S were explored by uniaxial compression, splitting tensile, and SEM-EDS analyses. Results show that STF had the most pronounced influence on mechanical strength enhancement. Specimens with 1.5 vol% STF exhibited high toughness, while the hybrid fiber system markedly improved uniaxial compressive strength (UCS), with SF acting as a supplementary modifier. At 0.2 vol% PPF, 1.5 vol% STF, and 10 wt% SF, UCS and splitting tensile strength (STS) augmented by 3.4 MPa and 0.38 MPa, respectively. SF improved matrix compactness and stiffness, significantly increasing the elastic modulus and reducing peak strain. The hybrid system produced a greater modulus increase than single-fiber shotcrete, demonstrating strong synergy. SFHF-S system inhibited rapid crack propagation through a "stepwise crack inhibition and continuous energy dissipation" mechanism, leading to complex failure modes characterized by interwoven tensile and shear cracks and narrower primary cracks. Increasing the SF content reduced pore depth, width, and connectivity within the matrix. Overall, SFHF-S exhibits superior