Accelerator for concrete spraying construction and preparation method thereof

Abstract

The invention discloses a quick-setting agent for shotcrete construction and a preparation method thereof, relates to the technical field of concrete additives, and is prepared from the following raw materials in parts by weight: 35-45 parts of polyglutamic acid, 35-45 parts of polyethylene glycol 20-25 parts of methyl ether, 15-20 parts of superfine wollastonite powder, 5-10 parts of trimethylolpropane triacrylate, 5-10 parts of cationic polyacrylamide, 1-10 parts of trimethylolpropane triglycidyl ether 5 parts, 1-5 parts of microcrystalline cellulose, 0.5-2 parts of asphalt emulsifier, 0.5-2 parts of hydrogenated castor oil. The quick-setting agent prepared by the present invention belongs to the solid non-alkali type accelerator. The solid form of existence avoids the problem that the liquid accelerator is easy to precipitate and precipitate after the storage time is too long, thereby affecting the quick-setting effect. The existence form of the non-alkali type avoids The hidden dangers of alkali-aggregate reaction and corrosion of steel bars exist in the use of alkali-containing accelerators.

Description

Technical field: [0001] The invention relates to the technical field of concrete additives, in particular to an accelerator for shotcrete construction and a preparation method thereof. Background technique: [0002] Shotcrete is a construction method of spraying and pouring fine stone concrete with a pressure spray gun. It is often used for pouring tunnel linings, walls, ceilings and other thin-walled structures or linings of other structures and protective layers of steel structures. Shotcrete is to put pre-prepared cement, sand, gravel, water and a certain amount of admixture into the sprayer, use high-pressure air to send it to the nozzle and mix it with the accelerator, and spray it to the rock at a high speed. or concrete surface. [0003] At present, accelerators are usually alkali-containing accelerators, among which aluminate accelerators are relatively effective in wet-mix shotcrete projects, and the setting time is shorter than that of alkali-free accelerators. T...

AI Technical Summary

Problems solved by technology

The main component of the commonly used alkali-containing accelerator is sodium metaaluminate, which is a supersaturated solution with poor stability. It is easy to precipitate and precipitate in a low temperature environment or after a long storage time, which is not conducive to the construction in a low temperature environment and the storage of the accelerator.

[0004] In addition, the alkaline substances in the alkali-containing accelerator will chemically react with certain active minerals (activated silica, activated alumina, etc.) in the concrete aggregate to generate swelling substances (or water-swelling substances) that cause internal The phenomenon of cracking due to self-expansion stress, thereby reducing the durability of concrete

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