Blending amount

Generally 5-10% da quantidade de materiais cimentícios.

The mixing method of silica fume is divided into internal mixing e external mixing.

1. Mistura interna: sob a premissa da mesma quantidade de água, 1 part of silica fume can replace 3-5 partes de cimento (peso) and keep the compressive strength of concrete unchanged while improving other properties of concrete.
2. External mixing: a quantidade de cimento permanece inalterada, and the addition of silica fume significantly improves the strength of concrete and other properties. Concrete mixed with silica fume when there is a certain slump loss. Este ponto precisa ser observado no teste de proporção.

Silica fume must be used in conjunction with water reducing agents, it is recommended to compound fly ash and finely ground slag to improve its constructability.

When formulating concrete with silica fume, the general weight ratio with cementitious materials is:

• concreto de alto desempenho: 5-10%.
• concreto hidráulico: 5-10%
• Shotcrete: 5-10%.
• Auxiliar de bombeamento: 2-3%.
• piso industrial resistente ao desgaste: 6-8%.
• argamassa de polímero, argamassa de isolamento: 10-15%.
• Concretos refratários indefinidos: 6-8%. Antes de usar, please select the reasonable and economic mixing amount through experiment according to the actual needs.

Mixing method.

Silica fume concrete and castables should be made by the test room. Siga rigorosamente a proporção de construção. Silica fume should be added to the mixer immediately after the aggregates are fed. Existem dois procedimentos para adicionar.

1. Into the aggregate, followed by silica fume, mistura seca de cimento, and then add water and other admixtures.
2. Coloque em agregado grosso + 75% água + Fumaça de sílica + 50% agregado fino, misture para 15-30 segundos, depois coloque cimento + mistura + 50% agregado fino + 25% água, misture até ficar uniforme. O tempo de mistura é 20-25% ou 50-60 segundos a mais que o concreto comum. Nunca adicione pó de sílica no concreto já misturado.

Construction method

There is no significant difference between the construction method of silica fume concrete and ordinary concrete, but it is necessary to organize and vibrate densely during construction well. The early strength of silica fume concrete will make the final setting time earlier, que deve ser prestado atenção ao rebocar; ao mesmo tempo, the addition of silica fume will improve the viscosity of concrete and significantly reduce water secretion, tornando o reboco um pouco difícil.

Construction safety

Silica fume concrete construction safety should be strictly in accordance with the relevant national construction specifications for concrete projects, but because silica fume is light, it is strictly prohibited to throw the material from a height to prevent silica fume from flying.