Concrete composite air entraining agent, its preparation and use methods

Abstract

Belonging to the technical field of building materials, the invention discloses a concrete composite air entraining agent, its preparation and use methods. The composite air entraining agent is composed of sodium dodecyl sulfate (14-60%), beta-cyclodextrin (30-84%), Arabic gum (1-8%), and bone gum (1-10%). The component raw materials are stirred evenly by physical and mechanical mixing, thus obtaining the concrete composite air entraining agent. During use, the dosage of the air entraining agent accounts for 0.004%-0.03% of the weight of cement in concrete. The concrete composite air entraining agent provided by the invention has the advantages of wide raw material sources, simple production method and excellent product performance, can introduce a lot of small, uniform and stable bubbles into concrete, enhances the water-retaining property of green concrete, improves workability, reduces slump loss, also greatly improves the freeze-thaw cycling resistance, salt-freezing resistance and other durability indicators of concrete, and has small negative influence on the strength of a hardened body. The concrete composite air entraining agent provided by the invention can be used in reinforced concrete, lightweight aggregate concrete, artificial aggregate concrete, bridges, buildings, hydraulic engineerings, pavements and other structures.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a composite air-entraining agent for concrete. Background technique [0002] Modern engineering requires high strength, high fluidity and high durability for concrete. Careful use of a certain amount of air-entraining agent in concrete engineering can produce a certain amount of fine round closed air cells in fresh concrete, which can improve the workability of concrete, reduce segregation and bleeding of the mixture, and improve Concrete uniformity, durability is very beneficial. However, the addition of common types of air-entraining agents such as sodium alkyl sulfonate, lignosulfonate, etc., has a great negative impact on the strength of concrete due to the unreasonable structure of the introduced air bubbles (the air content of concrete increases by 1%. The compressive strength is reduced by 4%-6%, and the flexural strength is reduced by 2%-3%), whic...

AI Technical Summary

Problems solved by technology

These three types of air-entraining agents are currently the main air-entraining agents used in the Chinese market, but these three types of air-entraining agents have more or less defects: rosin resin air-entraining agents have poor solubility; The bubble wall is thicker, the accumulation of bubbles is strong, and the resistance between each other is large, so it cannot be effectively and evenly dispersed into the concrete; the bubble volume produced by dodecylbenzenesulfonic acid air-entraining agent is large and the bubble stability is poor

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