what are the characteristics of microsilica-pg电玩城

microsilica (or silica fume) is amorphous, powdered sio2 collected by specially designed dust collectors after the oxidization of silicon steam through smoke flue during the smelting of silicon iron and industrial silicon. the average particle size of silica powder is 1% of the average particle size of cement at a value of 0.1-0.15 m. the specific surface area is 15-27 m2/g, with strong surface activity.

physical and chemical properties of microsilica:

1, microsilica: appearance is gray or gray powder, refractory > 1600 ℃. bulk density: 200 ~ 250 kg/m3.

2. fineness of microsilica: the fineness of microsilica is more than 80% of the product with a fineness of less than 1 muric acid m, the average particle size is 0.1-0.3 muric acid, and the specific surface area is 20 ~ 28m2/g. the fineness and specific surface area are about 80 ~ 100 times of cement and 50 ~ 70 times of fly ash.

3, particle shape and the ore phase structure, silica fume in the process of formation, by phase transformation in the process of the effect of surface tension, formed an amorphous phase and amorphous and the surface is relatively smooth, some are more sphere aggregate particles stick together. it is a kind of specific surface area is large, active substances of very high ash. mixed with microsilica material, tiny globule can play the role of lubrication.

function of silica powder in concrete:

microsilica mixed with concrete can be fully dispersed, after filling in the gaps between cement particles, the slurry is more dense, micro silicon powder ash activity index of up to 110, effectively replace the coefficient of up to 3-4, the dragon is generated after the cement hydration of ca (oh) 2 has the strong absorption capacity, well developed calcium silicate gel formation, greatly enhance the strength of the concrete.

1. increase of strength: when the incorporation amount is 5-10%, the compressive strength of concrete can be increased by 10-50%, and the flexural strength can be increased by more than 10%.

2. increase the density: when incorporation of 10%, the anti-permeability will be increased by 5-8 times, and the anti-carbonization ability will be increased by more than 4 times.

3. increase of frost resistance: after 300-500 freeze-thaw cycles, the relative dynamic elastic modulus of concrete mixed with 10% silica powder reduces by 1-2%, while that of ordinary concrete after 25-50 cycles reduces by 36-73%.

4. increase the early strength: the compressive strength of r1 in the control group increased by 30%, and that of r3 increased by 40-50%.

5. increase the abrasion resistance and cavitation resistance: compared with ordinary concrete, the abrasion resistance of microsilica powder concrete is improved by 0.5-2.5 times and the cavitation resistance by 3-16 times. it is a good material for anti-wear repair and surface protection of hydropower station, reservoir and dam.