Work

Synergistic effects of fiber hybridization on the fracture toughness of seawater sea-sand concrete

Year: 2024

Type: article

Abstract: This study investigates the fracture behavior of fiber-reinforced seawater sea-sand concrete (FR-SWSSC), focusing on the impact of fiber hybridization on fracture toughness properties and potential synergistic effects. The study employed micro-fibers including short polypropylene (PPS), polyvinyl alcohol (PVA), basalt fibers (BF), and macro-fibers consisting long polypropylene (PPL) and twisted polypropylene (TPPL) fibers. To examine the synergistic influence of fiber size on the fracture behavior, this research employed two types of hybrid fiber reinforcements: one containing only micro-fibers and another incorporating both micro-fibers and macro-fibers. The results indicated that mono micro-fibers had no significant effect on the post-peak behavior of SWSSC. In contrast, macro-fibers, PPL and TPPL increased fracture energy by 144% and 93%, respectively. Micro-fiber hybridization not only significantly improved the flexural strength of SWSSC, but also improved the overall fracture performance including residual strength and fracture energy. Hybrid PPS/BF and PPS/PVA fibers led to considerable increases in fracture energy by 176% and 290%, respectively, compared to mono PPS. Micro- and macro-fiber hybridization exhibited a synergistic effect on fracture toughness. The combination of BF or PPS with PPL or TPPL fibers significantly improved fracture toughness. PPL/TPPL fibers bridge larger cracks, thereby activating micro-fibers for a positive synergistic effect. Additionally, the strong chemical bond of PVA and BF fibers with concrete matrix effectively strengthened the surrounding concrete matrix and improved the bonding of the macro-fibers. By exploring the synergistic effect of hybrid discrete fibers in enhancing the fracture performance of FR-SWSSC, this research promotes sustainable

Source: Construction and Building Materials

DOI: 10.1016/j.conbuildmat.2024.137845