Water-reducing metakaolin-based micro-expansion compacting agent and preparation method thereof

Abstract

The invention relates to a water-reducing metakaolin-based micro-expansion compacting agent and a preparation method thereof. The water-reducing metakaolin-based micro-expansion compacting agent comprises components A and B, wherein the component A is prepared from the following raw materials in percentage by weight: 85%-94.5% of metakaolin, 0.5%-5% of polycarboxylate water-reducer powder and 5%-10% of gypsum; the component B is prepared from lime; and the component B accounts for 1%-5% of total mass of the component A. The water-reducing metakaolin-based micro-expansion compacting agent has the advantages that (1) the working property of the concrete is significantly improved; (2) the volume stability of the concrete is improved; and (3) the early strength of the concrete is obviously improved.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a water-reducing metakaolin-based micro-expansion compacting agent and a preparation method thereof. Background technique [0002] The cement industry is a typical resource and energy-consuming industry, and it is an industry that pollutes the environment seriously. The production of 1 ton of cement needs to consume 1.1 tons of limestone and emit nearly 1 ton of CO2. In recent years, major industrially developed countries and regions in the world have attached great importance to the research and development of green building materials, and climate change has also sounded the alarm for people all over the world. Actively develop and utilize high-performance auxiliary cementitious materials, use low clinker to produce high-quality products, reduce energy consumption and material consumption, and reduce negative effects on the environment. Taking the road of...

AI Technical Summary

Problems solved by technology

[0005] 1) Due to the high specific surface area of ​​metakaolin (≥2300m 2 / kg) and layered structure, strong water absorption and layered structure is not conducive to the relative movement between particles, resulting in poor concrete work performance, which affects the pumpability and filling of concrete, and ultimately affects the later performance of concrete;

[0006] 2) Due to the high fineness of metakaolin, it is easy to agglomerate and difficult to disperse, which is not conducive to the exertion of the active effect of metakaolin

[0007] Single mixed metakaolin will significantly reduce the performance of concrete, and even affect the normal construction

In order to ensure the working performance of the concrete mixed with metakaolin, the current method is to use metakaolin and water reducer separately mixed into the concrete for use. This kind of method cannot make the metakaolin evenly dispersed in the cement concrete. The activity of metakaolin and its layered structure characteristics are not well utilized, so this method has no significant effect on improving the performance and strength of concrete in the actual application process

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