Physical and mechanical properties of silica fume concrete

  The specific surface area of the micro-silica fume is very large, and the wetting of the granule surface needs to be the most moisture, so that the fresh water on the freshly coagulated concrete is confined by the position of the micro-silica powder. It is difficult to have extra water in the concrete. Aspects, micro-silica fume particles blocked the pores of fresh concrete. Therefore, in the concrete infiltration of micro-silica fume, concrete drilling and water retention increased, but the mobility is greatly reduced, and the reduction in the degree of flow with the general increase in the use of silicon powder increases.

   The incorporation of micro-silica fume significantly increased the standard consistency of Portland cement. There are studies that save liquidity unchanged; per cubic meter of concrete for each adding 1kg of micro-silica fume, need to increase the water consumption of 1kg. Therefore, in order to ensure the strength of silica fume concrete and the necessary liquidity, in the concrete doped with micro-silica fume at the same time, must be beaten with superplasticizer. General domestic multi-purpose naphthalene superplasticizer, the amount of about 1%. High-strength concrete production, in order to reduce the water-cement ratio, sometimes water-reducing agent mixed with 2% -3%.