What Is The Function Of Special Micro-Silica Fume For External Wall Insulation Board
1. Adding method:
The construction mix ratio of silica fume concrete and castable shall be made by the laboratory. Construct in strict accordance with the mix ratio. In the mixing of silica fume concrete, silica fume should be added to the mixer immediately after the aggregate is added. There are two ways to join:
(1) Put in aggregate, then put in silica fume, cement and dry mix, then add water and other additives.
(2) Put in coarse aggregate 75% water, silica fume 50% fine aggregate and mix for 15-30 seconds, then put in cement admixture, 50% fine aggregate 25% water, and mix until uniform. The mixing time is 20-25% or 50-60 seconds longer than ordinary concrete. Never add silica fume to the mixed concrete.
2. Construction method:
There is no major difference between the construction method of silica fume concrete and ordinary concrete, but good organization and vibrating compaction are necessary in construction. The early strength of silica fume concrete will advance the final setting time, so care should be taken when plastering the surface; at the same time, adding silica fume will increase the viscosity of the concrete and greatly reduce bleeding, making it slightly difficult to plaster the surface.
3. Construction safety:
The construction safety of silica fume concrete should be carried out in strict accordance with the relevant national construction codes of concrete engineering, but because the silica fume is relatively light, it is strictly forbidden to throw materials at high altitude to prevent silica fume from flying.
Gansu Sanyuan Silicon Materials specializes in the production of micro-silica fume, micro-silica fume for refractory materials, and micro-silica fume for high-strength concrete. According to the different needs of customers, we can provide corresponding grades of high-quality micro-silica fume.
1. Factors affecting the price of micro-silica fume:
1. Reasons for index parameters such as content, quality, specifications and performance.
2. Production costs are related to changes in the market prices of raw materials.
3. Packaging and transportation and distance (from the factory to the destination).
4. External environmental factors, such as water and electricity supply, staff deployment, market factors, seasonal factors, etc.
2. Factors affecting market conditions and quotations of microsilica fume:
1. Market supply and demand, import and export, etc.
2. Varieties of micro-silica fume and silica fume. Such as: ferrosilicon and industrial silicon by-products, wollastonite powder and silica powder.
3. The color of the product and the degree of densification.
4. The production and management policy of the enterprise.
5. The difference between micro-silica fume for refractories and silica fume for concrete.
Micro-silica powder is a very active kind of HPC active mineral blending materials, and its main component is active SiO2. Silica fume is very small (<1μm) and has a high degree of separation. The mechanism of silica fume on the strength of HPC is: filling effect, pozzolanic effect, and chemical effect of pore solution.
The incorporation of silica fume into HPC increases the density of the HPC matrix, improves the bonding strength between cement paste and aggregate, reduces the adverse effect of Ca(OH)2 on the strength of HPC, and weakens the effect of ASR on HPC harm. The micro-silica powder in HPC is generally blended at 5%-15%, and the ideal blending volume is about 10%.
Concrete micro-silica fume is added to cement paste and concrete as an auxiliary cementing material, which can not only increase the degree of cement hydration, but also cause secondary hydration reaction with Ca(OH)2, and silica fume and its secondary Hydration products fill the harmful pores in the hardened cement paste and improve the interface performance between the hardened cement paste and the aggregate in the concrete, which will have a positive impact on the hardened cement paste and the microstructure of the concrete, thereby making its macro-mechanical properties particularly It has a very beneficial effect on their durability, and this is one of the basic tasks of cement and concrete material science, and the use of micro-silica fume can also reduce its environmental pollution and reduce its impact on the environment. pressure.