Effect of the addition of basalt fiber on life-cycle anti-cracking behavior of concrete

To evaluate the cracking resistance of basalt fiber reinforced concrete (BFRC) in different periods, including the curing period and the service period, restrained slab, restrained ring and three-point bending tests were conducted. In this investigation, various fiber lengths (i.e., 6 mm, 12 mm, and 18 mm) and fiber contents (ranging from 0.07% to 0.09%) were used to prepare BFRC. The plastic shrinkage behavior of BFRC was characterized by monitoring evaporation, bleeding, capillary pressure and plastic shrinkage strain, and the mechanism of the effect of the fibers in reducing plastic cracking was subsequently revealed. The restrained shrinkage strain in the steel ring was measured, and the cracking potential index (ΘCR) was assessed for all BFRC specimens. Furthermore, the fracture behavior, including the strain distribution and cracking process, was monitored by the digital image correlation (DIC) technique. The results showed that long basalt fibers (12 mm and 18 mm) effectively delayed the occurrence of the plastic settlement and reduced capillary pressure, resulting in a decreased crack width of concrete. The basalt fibers also led to a pronounced decrease in the ΘCR of the concrete, particularly at an early curing age (3 d). Moreover, the DIC test revealed that the crack occurrence was accompanied by a fuctuation in the strain field during the fracture process. Basalt fibers considerably slowed the formation and evolution of the strain stripes of the concrete under load, and consequently, the fracture energy and cracking resistance capacity of concrete can be improved by the addition of basalt fibers.

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Opracowanie rekordu ze środków MNiSW, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2024).