The use of inorganic ferrous–ferric oxide nanoparticles to improve fresh and durability properties of foamed concrete

Efforts to modify cement-based mixtures have continuously engrossed the interest of academics. Favourable impacts of nanoparticles, for instance, fine particle size and great reactivity, have made them be utilized in concrete. Foamed concrete (FC) is immensely porous, and its properties diminish with an increase in the number of pores. To enhance its properties, the FC matrix could be attuned by integrating numerous nanoparticles. The influence of ferrous–ferric oxide nanoparticles (FFO-NP) in FC was not discovered previously in the present body of knowledge. Thus, there is some uncertainty contemplating the mechanism to which extent the FFO-NP can affect the durability properties of FC. Hence, this study focuses on utilizing FFO-NP in the FC matrix. FC specimens with a density of 1000 kg/m³ were cast and tested. The objective was to assess the influence of different FFO-NP weight fractions (0.10%, 0.15%, 0.20%, 0.25%, 0.30%, and 0.35%) on durability properties such as drying shrinkage, porosity, water absorption and ultrasonic wave propagation velocity of FC. The results implied that the presence of a 0.25% weight fraction of FFO-NP in FC facilitates optimal water absorption, porosity, ultrasonic pulse velocity and drying shrinkage of FC. The presence of FFO-NP alters the microstructural of FC from loose needle-like into a dense cohesive microstructure of the cementitious composite. Besides, FFO-NP augments the FC matrix by filling the voids, microcracks, and spaces within the structure. Further than the ideal weight fraction of FFO-NP addition, the accretion of the FFO-NP was found, which caused a decline in durability properties.