A kind of alkali-free liquid accelerator and preparation method thereof

Abstract

The invention discloses an alkali-free liquid quick-setting agent and a preparation method thereof. The components of the quick-setting agent and the mass parts of each component are as follows: 30-60 parts of aluminum sulfate, 5-10 parts of calcium formate, methyl cellulose 1.0-3.5 parts, 0.8-1.5 parts of polyacrylamide, 0.2-1.0 parts of organic acid, 1-3 parts of triethanolamine, 0.15-1.08 parts of defoamer, 0.5-1.5 parts of phosphoric acid, 30-50 parts of water. Described organic acid is citric acid or oxalic acid. The defoamer is simethicone or polypropylene glycol. The non-alkali liquid quick-setting agent of the invention does not contain alkali metal ions, has no corrosive and irritating smell, stable quality, good adaptability, low dosage, fast coagulation speed and high strength. When the dosage is 1% to 3%, the cement can make the initial setting within 2 minutes and the final setting within 5 minutes; and it has good storage stability under the condition of -10℃~45℃.

Description

technical field [0001] The invention belongs to the technical field of concrete admixtures, and in particular relates to an alkali-free liquid quick-setting agent and a preparation method thereof. Background technique [0002] Accelerator is an admixture that makes cement concrete set and harden quickly. The main purpose of adding quick-setting agent is to increase the thickness of the first shotcrete spraying layer, shorten the time interval between two spraying coats, and improve the early strength of shotcrete so as to provide support resistance in time. Since production and use began in the 1930s, accelerators have become one of the important components of shotcrete due to their remarkable characteristics in quick setting and early strength. Especially with the increase in the number and scale of underground projects and their different functions, the accelerator is not only very important as a component of concrete, but also indispensable in some specific projects. It ...

AI Technical Summary

Problems solved by technology

[0003] Alkaline powder and alkaline liquid accelerators (commonly referred to as "traditional accelerators") have the following problems: ①Large loss of strength in the later stage; ②High alkali content, on the one hand, causes corrosion to construction personnel, Damage to human health, on the other hand, it may also cause concrete alkali-aggregate reaction, resulting in a decrease in concrete strength and durability; ③There is a lot of dust and a large amount of rebound; ④It is not convenient for sprayed concrete wet operations, etc.

[0005] Although the research on liquid alkali-free (low) alkali-free accelerators in my country has developed rapidly, and the proportion of engineering applications has also increased significantly, there are still some problems. For example, the dosage of accelerators is concentrated between 3% and 12%, which is relatively traditional. The dosage is too high at about 2%; there is still some instability in the adaptability of some accelerators to different types of cement, admixtures and admixtures; the price is too high