Alkali-activated slag cement retarder and application method thereof

Abstract

The invention discloses an alkali-activated slag cement retarder, which comprises by weight: 20%-30% of sodium chromate, 40-50% of sulfamic acid heterocyclic condensation compound, 20-30% of organosilicon surfactant. In the invention, charged negative and positive particles are introduced to prevent or slow down the movement speed of calcium ions under the influence of charge repulsion, or to reduce the electrostatic attraction of silicate ions, so that the generation of hydrate calcium silicate can be prevented. Thus, the delay of silicate ion polymerization can be realized. Meanwhile, the surface of a reaction product is adsorbed with the organosilicon surfactant, so that the delayed coagulation can be realized under double actions.

Description

technical field [0001] The invention relates to the field of building materials, in particular to a retarder for prolonging the solidification time of alkali slag cement. Background technique [0002] Alkali slag cement is composed of finely ground water-quenched blast furnace slag and alkali components. It is a new type of building cementitious material with excellent performance. More than 30 years of research and application have proved that it has a series of excellent properties: [0003] 1) Early-strength, quick-hardening and high-strength: Without using other special technological measures and adding other chemical admixtures, the strength of alkali slag concrete can reach 60-150MPa, and the strength of one day can reach 68MPa. Application, strength increased by 100% to 200% (compared to 28-day strength). [0004] 2) Low water demand: Generally, the standard consistency of alkali slag cement requires 17% to 22% of water. Therefore, under the condition of not using a...

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Problems solved by technology

[0011] Tests have proved that the retarding substances commonly used in ordinary Portland cement have no or little effect on the setting of alkali slag cement, and organic surface active substances and sulfurous acid alcohol residues have certain effects on the setting of alkali slag cement. However, for alkali slag cement with alkaline slag and alkali metal silicate or alkali metal hydroxide as the alkali component, its setting time can never meet the requirements of the relevant standards for the setting time of Portland cement. In view of this According to the current situation, the Soviet Union promulgated the "Technical Regulations for Alkali Slag Cemented Materials" in 1989. Article 2.10 stipulates that, except for the cemented materials with soluble sodium silicate as the alkali component, the initial setting time of all kinds of cemented materials shall not be earlier than 30 Minutes, the final setting shall not be later than 12 hours; at the same time, it is stipulated in Article 2.12 that: for cementing materials using soluble sodium silicate as the alkali component, the initial setting time shall not be earlier than 20 minutes, and the final setting shall not be later than 12 hours

It can be seen that the Soviet Union, the earliest researcher on this subject, did not find a way to effectively delay the solidification time of alkali slag cement, so the popularization and application of alkali slag cement was limited to a certain extent.

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