Micro-Silica Fume In Industrial Floor Concrete

Although micro-silica fume can improve the performance of freshly mixed and hardened concrete, it can also cause quality accidents if used improperly, so the following details should be paid attention to during use:

　　  (1) Due to the small particles of micro-silica fume, the large specific surface area, and the high water demand, when the concrete is mixed with micro-silica fume, it must be used in combination with superplasticizer to achieve good results.

　　  (2) There are two methods for mixing micro-silica powder into concrete: internal mixing and external mixing. Since the internal mixing method needs to reduce the amount of cement, this method is generally used in medium and low-grade concrete; the external mixing method does not reduce the amount of cement and is generally used in high-grade concrete.

        (3) The content of micro-silica fume in concrete should not be too high or too low. Generally, the content is 5%~10%. The beneficial effect of micro-silica fume in this range is the best, that is, not only micro-silica fume can replace cement. The effect is the best, various excellent properties are fully utilized, and adverse effects can be avoided. If the amount of micro-silica powder is more than 15%, the frost resistance of concrete will decrease.

　　 (4) Due to the high consistency of the micro-silica fume concrete, the slump of the concrete should be 2~3cm larger than that of ordinary concrete.

　　 (5) The mixing time of micro-silica fume concrete should be longer than that of ordinary concrete by 0.5~1min, in order to make the concrete mix more evenly, and prevent the micro-silica fume from forming agglomerates in the concrete and causing quality accidents.

　　 (6) After using micro-silica powder for concrete, early curing must be strengthened to prevent plastic shrinkage cracks in concrete.