Concrete expansion agent, concrete and preparation method thereof

Abstract

The invention discloses a concrete expansion agent, concrete and a preparation method thereof. The concrete expansion agent contains an expansion agent base material and an additive; the additive is meta-aluminate; the mass ratio of the meta-aluminate and the expansion agent base material is 1.0-3.0%. Each cubic meter of concrete contains 240-300 parts of cement, 15-63 parts of concrete expansionagent, 920-1110 parts of sand, 810-1000 parts of stones, 2.1-3.6 parts of water reducing agents and 160-175 parts of water in parts by mass. According to the technical scheme, the concrete expansion agent disclosed by the invention has the advantages that the concrete expansion amount can be increased, uniform expansion can be realized, and the concrete compactness can be enhanced.

Description

technical field [0001] The invention relates to the technical field of concrete, in particular to an expansion agent for concrete, concrete and a preparation method thereof. Background technique [0002] Prefabricated buildings are the main trend in the development of the construction industry, and the main structural form of prefabricated buildings is prefabricated concrete structures. The connection between the prefabricated components in the precast concrete structure will bring a lot of post-cast concrete. After the ordinary concrete is poured, it will inevitably shrink, and even lead to cracking, which will affect the safety of the structure. It is a commonly used economical, effective and practical method to add expansion agent to the concrete to make use of the expansion effect to compensate the shrinkage of the concrete to make shrinkage-compensated concrete with good volume stability. [0003] After the expansion agent is added to the concrete, the hydration of the...

AI Technical Summary

Problems solved by technology

This is because the hydration of the expansive agent usually occurs in the early stage, resulting in the reduction of free water in the concrete; the acicular or columnar ettringite and platy calcium hydroxide produced by hydration obviously increase the viscosity and yield shear stress of the cement paste, This reduces the fluidity of the fresh concrete

Expansive agents have an important impact on concrete compactness and hydration products. At present, the expansion of many expansive agents is difficult to control. The stress generated during expansion is too large, which reduces the compactness of concrete and the durability of concrete cannot be guaranteed.

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