physical, mechanical, durability and microstructure properties of lightweight concrete containing nanomaterials: a comprehensive review

In the construction industry, lightweight concrete (lwc) is a common structural and masonry element. its low density and significant thermal and acoustic insulation properties are why it is popular. recent studies have examined the potential benefits of adding different types of nanomaterials (nms) to lwc to improve its characteristics. recent decades have seen a notable increase in interest in the growing field of nanotechnology because of its innovative research and practical applications. the main objective of this review is the application of nms to enhance both the fresh and hardened properties of lwc. the effects of nms on the physical (thermal conductivity), mechanical (compressive, flexural, splitting tensile strength), microstructural, and durability properties of lwc were examined. this study found that nms improved the performance of lwc depending on the type and dosage of nms. it showed better mechanical, microstructural, and durability properties than the samples without nms. the addition of nanomaterials to concrete increases the pozzolanic content and surface energy of the cement composite, resulting in the durability enhancement of the cement composite. this article explored that incorporating nanoparticles into concrete enhances its strength by (12 to 58) %, (and 16 to 90) %, (16 to 55) % on the 28th day for the compressive, flexural, and splitting tensile strength respectively, but it reduces the workability of the cement composite. however, the excessive concentration of nanoparticles causes particle agglomeration, which decreases the strength and durability of the cement composite. thus, the review concluded that using nanomaterials in concrete is more favorable concerning the strength and durability advancement of the composite, as it improves their qualities and accelerates the hydration process. the knowledge gained from this review and the created database could be helpful to researchers and industry experts to facilitate the adoption of nms to enhance the performance of lwc.