Additive for activating flyash

Abstract

The invention discloses an additive for activating flyash, relating to a building material. The additive comprises the following components in parts by weight: 5-10 parts of naphthyl sulfonate formaldehyde condensate, 4-8 parts of sodium hexametaphosphate, 45-48 parts of gypsum powder and 38-42 parts of calcium hydroxide. The additive of the invention has the advantages that: 1, the additive has simple and feasible production process and is convenient to operation; 2, the alkalinity is extremely low, and no chlorides exist; 3, the additive accounts for 1.5-2% of gelled material, and has low doped amount and favorable price; and 4, due to the doped additive, the problem that the doped flyash reduces the initial strength of concrete is solved, and the later strength of the concrete can be ensured even and improved to some extent.

Description

technical field [0001] The invention relates to building materials, in particular to a fly ash activation additive for making concrete. Background technique [0002] Fly ash is a potentially active pozzolanic powder with the chemical composition SiO 2 、Al 2 o 3 and other metal oxides. The activity of fly ash is very low, not only lower than that of similar pozzolanic powder materials, but also lower than the hydration activity of slag. The main reason is that the chemical activity of the silica-alumina glass phase in fly ash is low. As a kind of industrial waste, fly ash itself only has potential activity. It must be activated with intensifying additives to make the activity manifest, so that it can replace 15-30% of cement in concrete, so as to reduce the production cost of concrete and improve the quality of concrete. Its comprehensive performance can also solve the pollution problem caused by fly ash discharge to the environment. [0003] Generally speaking, the use ...

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Problems solved by technology

[0003] Generally speaking, the use of fly ash to replace part of cement in concrete has an obvious disadvantage that the early strength of concrete will be reduced, especially when the content is high

At present, although the early strength of concrete can be solved by adding some activators and activators of fly ash, the late strength of concrete is low and the alkali content of concrete increases, which increases the possibility of alkali-aggregate reaction Or the amount of fly ash is increased, and the performance of concrete is improved, but the cost is not saved. Instead, it increases or creates new unfavorable factors for the stability, water consumption and pumping performance of fresh concrete.

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