Mechanical behavior and impact resistance of rubberized concrete enhanced by basalt fiber-epoxy resin composite

Although rubberized concrete is widely accepted as an eco-friendly building material, its engineering applications are far limited due to its relatively low strength. To address this deficiency, the current study examines the effect of enhancing the strength of rubberized concrete through incorporating basalt fibers (BF) and water-based epoxy resin (ER) at varying proportions. In this study, both experimental testing and numerical simulations were conducted to investigate the mechanical, impact, and abrasion resistance properties of BF-ER composite enhanced rubberized concrete (BERC) using 12 different mix ratios. The evolution of damage in BERC was investigated, and the reinforcing mechanism of the fiber-polymer composite was elucidated through micro-morphology and pore structure analysis. The results indicate that the compressive strength and impact resistance of rubberized concrete are significantly improved due to inclusion of BF-ER, with the former achieving up to 60 % higher than normal rubberized concrete, while the latter attains improvement of 100 %. Due to the energy-absorbing behavior of rubber particles and the enhanced bonding effect provided by fiber-polymer, BERC exhibited a ductile failure mode, characterized by development of more complex cracks. Inclusion of fiber polymer resin has strengthened the weak interfacial transition zone (ITZ) between rubber particles and cement paste, albeit at the cost of increased porosity caused by the multiple interfaces of BF. From the current study, the optimal dosages of BF and ER are determined to be 2 kg/m3 and 4 kg/m3, respectively. The research results have provided useful insights on the application of rubberized concrete in critical engineering structures that require impact and abrasion resistance.