Durable foam concrete and preparation method thereof

Abstract

The invention relates to durable foam concrete and a preparation method thereof. The concrete comprises the following raw materials: cement, fly ash, a rosin type foaming agent, a surfactant, modified alkali lignin, water, a water reducing agent and an early strength agent, wherein the modified alkali lignin is obtained by modifying alkali lignin by fluorine-containing acyl chloride under the condition of alkali catalysis. According to the preparation method, alkali lignin and fluorine-containing acyl chloride are taken as raw materials, modified alkali lignin macromolecules with a three-dimensional network structure and hydrophobic side chains are prepared through an esterification reaction, on one hand, a large number of phenolic hydroxyl groups, ether bonds and the like contained in the three-dimensional network structure form hydrogen bonds with a foaming liquid film, the viscosity and compressive strength of the liquid film are improved, moisture in the liquid film is locked, the liquid mobility is reduced, and a bubble wall film is prevented from thinning and cracking; on the other hand, the hydrophobic side chains not only can prevent bubbles from intersecting to form communicating holes to reduce the compressive strength, but also can be adsorbed on the surfaces of foam concrete holes to form coating films, so that water is difficult to permeate into the holes, and the water absorption rate is reduced.

Description

technical field [0001] The invention belongs to the technical field of foam concrete, and in particular relates to a durable foam concrete and a preparation method thereof. Background technique [0002] Foam concrete refers to the use of physical or chemical foaming technology to make a porous material containing a large number of small and uniform independent pores on the basis of cementitious materials. It has the advantages of light weight, energy saving and environmental protection, and good thermal insulation performance. In the actual production process, industrial waste such as fly ash can be widely used in foamed concrete, which not only saves cement and reduces costs, but also greatly reduces the land occupation of fly ash and environmental pressure. Therefore, fly ash foamed concrete has received more and more attention. . As a building material, strength is still one of the main properties of foam concrete. However, as the foam becomes lighter, the strength will ...

AI Technical Summary

Problems solved by technology

It can be seen that the mechanical strength of the foamed concrete prepared by using solid waste fly ash in the above-mentioned prior art has been improved to varying degrees, but their water absorption rate is also high, and the durability is still unsatisfactory or even declined.

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