A kind of highly stable non-alkali and chlorine-free liquid accelerator and preparation method thereof

Abstract

The invention provides a high-stability alkali-free chloride-free liquid accelerator and a preparation method thereof. the preparation method comprises the following specific steps: dissolving 47-55 parts of a quick-setting component and 3.5-6 parts of an inorganic early-strength component into 27.9-44.2 parts of deionized water at 75-90 DEG C, adding 1-3 parts of a solubilizing component, stirring and reacting for 0.5-1 h, adding 2.5-5 parts of a complexing component, stirring and reacting for 1.5-2.5 h, adding 0.2-0.6 part of an aqueous solution of a thickening component and 0.6-1 part of an organic early-strength component, stirring for 15-30 min, cooling to 50-60 DEG C, adding 1-1.5 parts of a pH regulation component, and stirring for 15-30 min so as to obtain the high-stability alkali-free chloride-free liquid accelerator. The prepared accelerator product has advantages of no corrosiveness or pungent smell, good cement adaptability, low mixing amount, short setting time, high early strength, no loss of long-term strength and good stability under the condition of minus 15-30 DEG C.

Description

Technical field [0001] The invention belongs to a concrete accelerator in the field of building materials, and particularly relates to a highly stable alkali-free and chlorine-free liquid accelerator and a preparation method thereof. Background technique [0002] With the development of my country's high-speed rail, expressway, subway and other infrastructure industries, and limited by the geomorphic characteristics of my country, there are more tunnel constructions for high-speed rail and expressway in the central and western regions, so the demand for shotcrete is increasing year by year. The concrete accelerator is an essential part of shotcrete, and its effect directly affects the quality of shotcrete. The technical level of shotcrete is mainly reflected in the research and application of accelerators. Therefore, the research on sprayed concrete admixture materials at home and abroad put the accelerator in a very important position. [0003] The accelerator for shotcrete is d...

AI Technical Summary

Problems solved by technology

Among them, the powder accelerator and the alkaline liquid accelerator have the disadvantages of large dust in the working environment, strong corrosion, large rebound, large loss of strength in the later stage, and poor durability, while the non-alkali liquid accelerator does not have these defects.

[0004] The patent document with the publication number CN102992677A discloses a non-alkali liquid quick-setting agent, which uses aluminum sulfate as the quick-setting component, and organic amines and polyols as stabilizers, but its stabilizing component dosage is relatively large, which affects the early strength. The negative impact is great, and it does not contain other stabilizing aids, and the stability of the accelerator is also poor

Similarly, in the quick-setting agents disclosed in the patent documents with publication numbers CN104370489A, CN104446090A, CN103664034A, and CN103553406A, about 6-10% of alcohol amines have been added, which will also have a relatively large negative impact on the early strength.

Publication No. CN104891852A discloses only about 2% alcohol amine substances in the quick-setting agent disclosed in the patent literature, but it also does not have other stabilizing aids, and the stability is relatively poor

Publication No. CN103396027A discloses ammonia water as the early strength component of the non-alkali liquid accelerator in the accelerator disclosed in the patent literature, but the use of ammonia water will have a negative impact on the human body

Publication No. CN104108894A discloses quick-setting agent with 5-25% magnesia added, because there is no substance reacting with it, so there will be problems in its solubility, and the addition of free magnesia will affect the concrete produce certain adverse effects on stability

[0005] To sum up, the current stable components of alkali-free liquid accelerators are basically DETA, alcohol amines or polyols, but there are the following defects: EDTA and aluminum ions are quantitatively complexed, if alcohol amines and polyols are mixed If the amount is small, its ability to complex and stabilize is limited. If the amount is large, the early strength will be greatly negatively affected

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