Influence of Nano‐Particles on the Flexural Fatigue Property of Concrete Made From All‐Solid‐Waste Cementitious Materials

ABSTRACT To reduce CO 2 emission and promote the resource utilization of solid waste materials, this paper uses steel slag, slag, and desulphurized gypsum to replace cement completely, and uses nano‐SiO 2 and nano‐CaCO₃ to replace steel slag to prepare solid waste concrete (SWBC), and the strength and fatigue properties of SWBC with nanoparticles are studied. The macroscopic test results show the strength and fatigue life of SWBC are improved by nanoparticles. When the stress level was equal to 0.6, adding 2% nano‐SiO 2 and 1% CaCO 3 enhanced the theoretical fatigue life of SWBC by 8.42 and 6.30 times, respectively. Microscopic tests show nanoparticles can generate more C‐S‐H gels with low Ca/Si in SWBC, significantly reduce the internal porosity of SWBC, and optimize the fatigue performance of concrete. The nanoparticles can play the role of crystal nucleus, accelerate the silica‐aluminum polymerization reaction, generate more hydration products and make structure denser.