The filling effect principle of Ewende micro silica powder mainly includes the following aspects:
Physical filling: the particle size of microsilica powder is very small, with an average particle size of 0.1-0.3μm and a specific surface area of 20-28m²/g, which is about 80-100 times that of cement and 50-70 times that of fly ash. Therefore, microsilica powder can well fill the pores between cement particles, make the paste more dense and reduce the porosity, so as to improve the strength and durability of concrete.
Chemical bonding: microsilica powder has high activity, which can have secondary hydration reaction with calcium hydroxide (Ca(OH)₂) produced by cement hydration to generate calcium silicate (C-S-H) gel.C-S-H gel is the main source of strength of cement stone, and its generation can improve the strength and durability of cement stone. In addition, microsilica powder can react with other cement hydration products to further improve the performance of concrete.
Volcanic ash effect: The main component of microsilica powder is silicon dioxide (SiO₂), which has volcanic ash activity. In cement concrete, microsilica powder can react with calcium hydroxide produced by cement hydration to generate calcium silicate gel, thus improving the strength and durability of concrete. This volcanic ash effect allows the concrete to gain high strength at an early stage and the strength will continue to increase with time.
Microaggregate effect: The particle size of microsilica powder is very small, equivalent to a few hundredths of the particle size of cement. Therefore, microsilica powder can be used as a kind of microaggregate to fill in between the cement particles and improve the compactness and strength of concrete.
