The use of micro-silica fume as adulterating agent in the concrete industry is the earliest, most successful and widely used fields in the comprehensive utilization of micro-silica fume.
Because microsilica has the characteristics of fine particles, large specific surface area, high purity of SiO2, strong volcanic ash activity and other physical and chemical characteristics, adding micro-silica fume into concrete as admixture improves the performance of concrete in many aspects. Such as significantly improving the plastic concrete adhesion properties and cohesion, significantly reduce the rebound, increase the thickness of shotcrete one-time molding, shorten the construction period, and save project cost.
When require special high-strength concrete, micro-silica fume is used as blending material to formulate high-strength concrete, and its strength grade can reach 100 MPa. Many important high-rise buildings abroad, such as the South Wak Building in the United States and the BfG Building in Frankfurt, Germany, have all used microsilica as reinforcing additives for concrete. In some important concrete water conservancy and hydropower projects in developed countries such as offshore oil drilling platforms, large-span bridges, tunnels and other projects, the addition of micro-silica fume can improve anti-seepage, anti-abrasion, anti-corrosion and other properties.
Silica fume concrete is used in highway pavements and aircraft runways, which can greatly improve the early strength and wear resistance of concrete. In the maintenance and repair of highway pavement, it can be opened to traffic in advance to increase economic efficiency.
In Europe and the United States, 75% of sprayed concrete is mixed with microsilica, while in Norway and Sweden, microsilica is an essential material for shotcrete.