Special admixture for self-compacting concrete as well as preparation method and application of special additive

Abstract

The invention provides a special admixture for self-compacting concrete and a preparation method and application thereof, and the special admixture for self-compacting concrete comprises the following materials in parts by weight: 370-400 parts of polycarboxylic acid water-reducing ether; 100 to 130 parts of polycarboxylic acid pure slump retaining type ether; 0-20 parts of borax; 8 to 12 parts of sodium gluconate; 8-12 parts of white sugar; 3-7 parts of sodium citrate; 9-27 parts of polyethylene glycol; 0.1 to 0.4 part of polyacrylamide; 0.1 to 0.5 percent of hydroxyethyl methyl cellulose ether; 0.1 to 0.5 part of a defoaming agent; 0.2 to 0.6 part of an air entraining agent; and 430-460 parts of water. The admixture special for the self-compacting concrete provided by the invention is large in flowability and good in wrapping, can solve the problem of engineering structures which cannot be constructed or are difficult to construct by using common concrete, and meanwhile, avoids the engineering quality problem caused by vibration leakage and excessive vibration of the common concrete. By adopting the admixture special for the self-compacting concrete provided by the invention, when the concrete is constructed, time and labor are saved, noise is avoided, the construction speed is high, the labor intensity of workers is reduced, and energy is saved.

Description

technical field [0001] The invention relates to a special admixture for self-compacting concrete and its preparation method and application. Background technique [0002] Self-compacting concrete refers to the concrete that can flow and compact under its own gravity, and can completely fill the formwork even if there are dense steel bars, and at the same time obtain good homogeneity and do not require additional vibration. [0003] The principle of preparing self-compacting concrete is to reduce the yield stress of concrete enough to be overcome by the shear stress generated by its own weight through the selection and matching of admixtures, cementing materials, coarse and fine aggregates, and careful mix ratio design to make the concrete fluidity At the same time, it has sufficient plastic viscosity to suspend the aggregate in the cement slurry without segregation and bleeding problems. It can flow freely and fully fill the space in the formwork to form a dense and uniform ...

AI Technical Summary

Problems solved by technology

[0005] At present, the admixtures on the market are mainly through adjusting the mix ratio, and the high-fluidity concrete produced by using ordinary high-performance concrete admixtures is not self-compacting concrete in the true sense, while ordinary high-performance concrete admixtures simply increase the flow inability to meet the growing needs of users and need to be improved

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