Silica fume is a highly pozzolanic by-product of the ferrosilicon industry that is used to improve the mechanical and durability properties of concrete. It can be used as a standalone element in concrete or mixed with Portland cement and silica fume.
- High early compressive strength
- High tensile flexural strength and modulus of elasticity are all advantages of using silica fume.
- Permeability to chloride and water intrusion is quite low.
- Longer life span
- Toughness has improved
- Abrasion resistance on decks, floors, overlays, and marine structures has been improved.
- Superior chemical resistance to chlorides, acids, nitrates, and sulphates, as well as life-cycle cost-efficiency
- Increased bond strength
- Low permeability and high electrical resistance
Benefits of silica fume in concrete include:
(1) Silica fume is inorganic neutral filler with extremely stable physical and chemical properties. It contains no crystalline water, does not participate in the curing reaction, and has no effect on the mechanics of the reaction.
(2) Strong resin infiltration, good adsorption performance, easy mixing, and no agglomeration phenomena
(3) The silica fume size distribution is acceptable, with high densification, hardness, and wears resistance. The tensile strength, compressive strength, impact strength, and wear resistance of cured goods may all be considerably improved, and the abrasion resistance can be raised by 0.5 to 2.5 times.
(4) It can improve thermal conductivity, adhesive viscosity, and flame retardancy.
(5) The exothermic peak temperature of the epoxy resin curing process can be lowered, as well as the linear expansion coefficient and shrinkage rate of solidified products, to eliminate internal stress and prevent cracking.
(6) It can effectively decrease and remove precipitation and stratification due to the fine grain size and suitable distribution of silica fume.
(7) Pure silicon powder with low impurities and steady physical and chemical properties, ensuring good insulation and arc resistance in the curing material.
(8) Silica fume’s chemical composition is silica (SiO2), which is an innocuous substance. Most acids and alkaloids don’t react with it. On the surface of things, the silicon powder is evenly spread and covered. It offers high corrosion resistance and a 3-16 fold increase in cavitations resistance.
(9) low bulk density (0.2–0.8) or 1–2.2). Minimizing the quantity of loading and saving the amount of polymer, it can lower the cost of the product as a polymer filling material.
(10) Micro silica fume has a good frost resistance, with a relative elastic modulus of 10 to 20% after 300-500 quick freeze-thaw cycles, compared to 30 to 73 percent for conventional concrete after 25-50 cycles. As a result, concrete’s frost resistance can be increased.
(11) Early strength, micro silica concrete can reduce the induction time and have early strength characteristics.
Silica fume in concrete disadvantages:
- Shrinking due to dryness.
The shrinkage rate of silica fume concrete is high, especially early dry shrinkage, making it easy to crack in the application of silica fume concrete, reducing the overall strength and usage effect. After construction, for example, strengthening water and sprinkler maintenance can help to mitigate this issue, although cracks are unavoidable in many construction projects.
- The construction is challenging.
Concrete workability is an important criterion in the design of concrete mix proportions; silica fume concrete workability is poor, making it difficult to make close-grained concrete vibrate and plaster, affecting the smoothness of concrete quality and surface uniformity.
- it’s simple to create temperature fractures.
When concrete with silica fume develops early strength, the corresponding concrete hydration heat dissipates quickly, resulting in a rise in concrete hydration heat temperature, making it easy to produce high-temperature stress in the concrete, causing stress concentration at the top of the dry shrinkage crack, causing dry shrinkage cracks to extend even through the formation of transfixion cracks.
Looking for silica fume suppliers so visit bisley.biz
Throughout the Middle East, Asia, Australia, and New Zealand, Bisley and Company is a significant provider of Silica Fume (or Microsilica). Silica fume is a powder made up of almost spherical particles that are 100 times smaller than a grain of cement.