The effect of nano-SiO2 on concrete properties: a review

Abstract

In recent years, the addition of nanometer materials to concrete materials has attracted a group of increasing number of scholars’ research interests, and nano-SiO2 is one of the research hotspots. In this paper, we briefly introduce the influence of nano-SiO2 on setting time, slump, shrinkage, durability and mechanical properties of concrete. In addition, this review also includes the microstructure measured by scanning electron microscope (SEM) and the content of various hydration products obtained by X-ray diffraction (XRD). The result shows that the setting time of nano-SiO2 concrete is shortened, the slump is reduced and the shrinkage is improved owing to the high activity and nucleation of nano-SiO2. The improvement effect of nano-SiO2 on concrete is remarkable, especially in the aspect of enhancing the durability of concrete. It should be noted that nano-SiO2 shows limited improvement in the mechanical properties of concrete. In the end, this literature summary explains the macro performance of nano-silica modified concrete through microstructure.

Advances of graphene- and graphene oxide-modified cementitious materials

“…The addition of nanomaterials into the cementitious materials not only greatly improve the mechanical performance but also lead to better durability and microstructure of the cementitious materials [16,17]. Nanoparticles with most extensive applications in cementitious materials [18][19][20] and high reactivity can accelerate hydration and can fill microscopic pores in the matrix to increase the compactness of the cementitious materials [21][22][23][24]. For example, carbon nanotubes (CNTs) as a microscopic fiber can significantly enhance the strength [25], toughness [26], and durability [27] of cementitious materials and will affect the electrical [28] and thermal [29] conductivity, making cementitious materials multifunctional and smart [30][31][32][33].…”

Hydration activity, crystal structural, and electronic properties studies of Ba-doped dicalcium silicate

“…Therefore, low-grade ore should be used in cement manufacture in point of view of sustainable development. High belite cement has a wide application potential due to its low energy consumption, low CO 2 emission, and excellent durability performance [3][4][5][6][7][8]. Compared with Ordinary Portland cement, high belite cement consists of more than 40% dicalcium silicate (C 2 S) [9,10].…”

Antibacterial Fibers Containing Nanosilica with Immobilized Silver Nanoparticles

“…application in many fields of science and industry. They are used for self-cleaning coatings [15] for high-durable superhydrophobicity and antibacterial activity [16], for improvement in thermal performance of firefighter protective clothing [17,18], and improved durability and mechanical properties of concrete [19]. For this reason, research on novel methods of nanosilica production has been undertaken, which would allow for a significant improvement in the physicochemical properties of particles, as well as better control over their size, shape, and porosity.…”