Because of its high activity, water-reducing and reinforcing properties, micro-silica fume plays an important role in the construction cement mortar concrete industry. Therefore, it is widely used in construction, metallurgy, chemical industry, cement and other industries.
The raw silica fume is lighter, transportation is more difficult and cost is high. The densified technology has greatly reduced the labor cost and good working environment.
Undensified silica fume can be used a simple method, namely: 40 g water: 60 g silica fume: 0.2g dispersant (triple or P530), after full stirring, poured on the glass plate, natural flow, measuring flow area, if the average diameter is greater than 130MM, the fluidity is good, but it is better to do an amorphous test block, according to the volume of water, the final judgement is good or bad. But now domestic silica fume can achieve this standard too little.
Measuring methods for densified silica fume fluidity
The above method can not be used for densified silica fume. Only amorphous specimens are determined: amorphous specimens are tested without fixed formula. Examples are given: 70% bauxite clinker, 20% 0-325 mesh bauxite powder, 3% silica fume, 7% bauxite cement, 0.2% sodium hexametaphosphate, 8-9% water. Vibration flow values of castable slurry are measured by jumping table or shaking table, minimum water flow values is the best.
Precautions and details for measuring the fluidity of micro silica fume:
1. The silica fume should be stirred to liquid state completely. If the microsilica powder is still viscous after stirring for a long time, it is proved that the fluidity of the selected micro silica fume sample is poor (the factors affecting the fluidity of the silica powder). The following experiments are not necessary.
2. Must place the glass plate on horizontal desktop, so that when poured, the microsilica slurry can diffuse more evenly, which is conducive to the next measurement work.
3. The fluidity of different silica fume is different. It is suggested that the samples of micro-silica fume should be taken separately, averagely and mixedly for measurement.