Investigation of cementitious composites reinforced with metallic nanomaterials, boric acid, and lime for infrastructure enhancement

Abstract

<abstract> <p>Nanomaterials integration within construction materials could promote the generation of more sophisticated structural materials, as it imbues reinforcement at the nanoscale. This research adopted experimental approaches to assess the influence of metallic nanomaterials on the performance of cementitious composites with various ratios of boric acid (1%, 3%, and 5% by sand's weight) and lime (0.5%, 1.5%, and 2.5% by sand's weight), respectively, for use in construction infrastructure facilities. This research provides valuable insight into the potential of using boric acid and lime as well as metallic nanomaterials to strengthen cement-based composites. Initial curing stages revealed a notable decrease in compressive strength attributed to the inhibitory effects of boric acid and lime on cement hydration. However, the introduction of TiO<sub>2</sub> nanoparticles demonstrated significant enhancements in compressive strength and durability. Statistical analysis emphasized the significance of nanomaterials in augmenting compressive strength, with implications for long-term performance. This study has shown that the addition of nano-titanium dioxide TiO<sub>2</sub> can significantly enhance the compressive strength of Portland cement mortars, particularly when used in conjunction with appropriate ratios of boric acid and lime. The results of the 7 days test indicated that the inclusion of boric acid and lime in the cement mortars significantly decreased the compressive strength. However, the addition of nano-TiO<sub>2</sub> to cement mortars containing 1% boric acid and 0.5% lime resulted in a 31-fold increase in compressive strength compared to cementitious composites without nano-TiO<sub>2</sub>. In contrast, the compressive strength significantly increased by 1.2 times, 85.3 times, and 65.1 times, respectively, after 56 days for the addition of boric acid (1%, 3%, and 5%) with lime (0.5%, 1.5%, and 2.5%), respectively, in the presence of nano-TiO<sub>2</sub>, compared to the 7 days strength. The results also illustrated that, in general, the incorporation of various types of nano-TiO<sub>2</sub> into cementitious composites containing boric acid and lime increases their compressive strength as the ratios of boric acid and lime increase, as long as sufficient curing time is allowed.</p> </abstract>