Fracture performance is a critical design parameter in advanced concrete structures, strongly influenced by material composition. This study evaluates the influence of three supplementary cementitious materials—silica fume (SF), ground granulated blast furnace slag (GGBFS), and quarry stone powder (QSP)—on the fracture response of high-performance hybrid fiber-reinforced concrete (HPHFRC). A series of 180 notched beam specimens were tested using three fracture characterization approaches: Work of Fracture Method (WFM), Size Effect Method (SEM), and Boundary Element Method (BEM). Key fracture parameters, including fracture energy (, ), fracture toughness (), characteristic length (), fracture process zone length (), and reference crack length (), were analyzed alongside microscopic observations and regression modeling. Results showed that 10 % SF significantly improved fracture energy and toughness but induced a more brittle fracture mode due to strong fiber–matrix bonding. Conversely, ternary and quaternary mixtures containing GGBFS and QSP reduced peak fracture resistance but improved ductility and crack stability by promoting fiber pullout and interface softening. The quaternary blend containing 10 % SF, 15 % GGBFS, and 10 % QSP alongside cement demonstrated the most balanced performance, offering a favorable trade-off between energy dissipation and inelastic deformation. The study also highlights meaningful consistency and complementary trends across WFM, SEM, and BEM methods, with / ratios averaging above 60—underscoring the substantial post-peak energy dissipation capacity of macro synthetic fiber-reinforced systems. These findings contribute to the mechanics-based optimization of sustainable, fracture-tolerant fiber-reinforced concretes for use in fracture-critical infrastructure.

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