With the addition of fly ash, the carbonation depth of concrete increases with the increase of total content. When the total content is constant, with the increase of fly ash content, the slag content decreases and the carbonation depth of concrete increases. And there is an optimal mixture ratio between them, which makes the carbonation resistance of concrete the best.

Fly ash will react with calcium hydroxide in concrete, reducing the alkalinity of concrete. Carbonization is the reaction between carbon dioxide in the air and calcium hydroxide in concrete. Now calcium hydroxide is consumed by fly ash, and its carbonation resistance naturally drops seriously.

Concrete, referred to as "concrete" for short, refers to the general name of engineering composite materials bonded by cementing materials. Generally speaking, the term concrete refers to cement as cementing material and sandstone as aggregate; Cement concrete, also known as ordinary concrete, is made by mixing and stirring water (including admixture and admixture) in a certain proportion, which is widely used in civil engineering.

Concrete has the characteristics of abundant raw materials, low price and simple production technology, so its consumption is increasing day by day. At the same time, concrete also has the characteristics of high compressive strength, good durability and wide range of strength grades. These characteristics make it widely used, not only in various civil engineering, but also in shipbuilding, machinery industry, marine development, geothermal engineering and so on. Concrete is also an important material.