Method for preparing high-strength permeable concrete by high-iron low-quality coal ash

Abstract

The invention belongs to the field of building materials, and particularly relates to a method for preparing high-strength permeable concrete by high-iron low-quality coal ash serving as a main raw material. Compared with traditional cement-based permeable concrete, the method has the advantages that the activity of the low-quality coal ash is improved by pretreating the coal ash, the use ratio ofthe coal ash is 100%, the adding amount of the coal ash in a product is not lower than 80%, mineral consumption and CO2 emission are reduced, secondary products are avoided, waste is used, environments are protected, the potential destructive effect of iron on the concrete is reduced by pretreatment, the pigment effect of iron in the coal ash is sufficiently achieved, red permeable concrete can be prepared without adding pigments, the early strength of a product mainly prepared from the low-quality coal ash is improved, the compressive strength of standard curing 1d can reach 20MPa, the strength of standard curing 3d can reach 30-40MPa, permeable rate is not lower than 2mm / s, special curing is omitted, strength development is rapid, production cycle is shot, and production cost can be greatly reduced.

Description

technical field [0001] The invention belongs to the field of building materials, and in particular relates to a method for preparing high-strength permeable concrete by using low-quality fly ash with high iron content. Background technique [0002] In recent years, with the rapid development of the economy, the speed of urbanization has accelerated, and cement and concrete structures have dominated urban construction. However, this has also led to problems such as urban water accumulation, waterlogging, and heat island effect. Therefore, the construction concept of "sponge city" was proposed. Sponge city means that the city can absorb water, store water, infiltrate water, purify water when it rains like a sponge, and "release" the stored water and use it when needed. Permeable concrete is an important guarantee for the "sponge city" construction system. On the one hand, it alleviates the problem of road water accumulation and provides safety guarantee for vehicles and peopl...

AI Technical Summary

Problems solved by technology

[0005] In the existing patents and documents, metakaolin, high-titanium slag, red mud, fly ash and other industrial solid wastes have been used as the main raw materials to prepare cementless concrete or products (patent: "a reinforced geopolymer and its preparation method (ZL 201610141817.X), "an alkali-activated high-titanium slag permeable product and its preparation method (CN201711015613.2)", "a modified alkali-activated gelling material and its preparation method (CN201510810774. 5)", "A preparation method for geopolymer-based permeable bricks" (201711452058.X), "A method for preparing geopolymer concrete using coal-fired sulfur-fixed ash (201710965575.0)", "A pulverized coal Gray construction waste permeable bricks and their preparation methods (201610652070.4)", etc.), but for cementless concrete with fly ash added, there are shortcomings of low early strength and low addition amount, and no low-quality fly ash with high iron content has been found Preparation of permeable concrete materials