Synergistic effects of multi‐scale basalt fibers on the mechanical properties of marine concrete: From short‐term enhancement to long‐term durability

Abstract With the rapid development of marine and offshore infrastructure construction, enhancing the durability and mechanical properties of concrete in harsh marine environments has emerged as a critical engineering requirement. This study systematically investigated the synergistic enhancement effect of multi‐scale basalt fibers on the short‐term mechanical properties of marine concrete and its long‐term durability under simulated seawater wetting‐drying cycles. The results indicated that the optimal mixing proportions (Groups B10N01 and B15N02) significantly enhanced the comprehensive performance of marine concrete. The 28‐day compressive strength of the two groups increased by 7.33% and 8.33%, respectively, compared to the undoped fiber group, and flexural performance also showed marked improvement. Long‐term durability research showed that after 270 days of corrosion exposure, the fiber strengthening effect in Group B15N02 remained stronger than the environmental degradation, maintaining excellent performance stability. At the micro‐scale, the three‐dimensional network structure formed by multi‐scale fibers effectively blocked the transport of corrosive media and optimized the structure of the interfacial transition zone. Through the synergistic mechanism of “micro‐fibers suppressing fracture propagation and macro‐fibers enhancing toughness,” performance improvements were achieved across all scales.