High-magnesium waste rock powder-based composite mineral admixture and its application in low-strength concrete

Abstract

The invention discloses a high-magnesium waste stone dust-based composite mineral admixture, and applications thereof in low-strength concrete. The high-magnesium waste stone dust-based composite mineral admixture is prepared via following steps: (1) high-magnesium waste stone, wet discharged fly ash, and manganese residue are dried until water content is lower than 1.0%; and (2) by weight, 70 to 85 parts of the dried high-magnesium waste stone, 10 to 20 parts of the dried wet discharged fly ash, and 0 to 10 parts of the dried manganese residue are mixed, and an obtained mixture is smashed into powder with a specific surface area ranging from 480 to 600m2 / kg so as to obtain the high-magnesium waste stone dust-based composite mineral admixture. According to the high-magnesium waste stone dust-based composite mineral admixture, morphology effects and filling effects of high-magnesium waste stone powder are used so as to increase compactness of concrete mixtures, and increase fluidity of concrete; slump loss is less; less additives such as polycarboxylic acid are absorbed; concrete early-stage strength development is accelerated, and later-stage development is stabilized. And in addition, the high-magnesium waste stone dust-based composite mineral admixture can be applied to concrete together with high-magnesium waste stone coarse and fine aggregates so as to increase utilization ratio of high-magnesium waste stone greatly.

Description

technical field [0001] The invention belongs to the field of building materials, and in particular relates to a high-magnesium waste rock powder-based composite mineral admixture and its application in low-strength concrete. Background technique [0002] With the continuous development of the cement and concrete industry, a large amount of high-quality limestone resources are constantly being consumed, and the waste minerals in limestone mines are also increasing year by year. These wastes are piled up on the surface for a long time, which not only takes up a lot of land resources, but also has potential impact on the environment. Hazards, such as causing soil and water environment pollution, destroying vegetation, etc. Therefore, how to deal with limestone mine wastes, thereby saving stockpiled land and reducing environmental pressure, is an important issue to be solved urgently by the cement industry. [0003] As we all know, when mining limestone mines, high-quality lime...

AI Technical Summary

Problems solved by technology

[0010] (4) Wet fly ash is mixed with water and bottom ash, resulting in low activity, high impurity content, and poor homogeneity, which limits the popularization and application of wet fly ash, and may also have potential Hazardous

At present, a large amount of untreated manganese slag is directly accumulated for a long time, which will cause serious pollution to the surrounding environment.

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