Study on Carbonation and Chloride Ion Erosion Resistance of Concrete Used in Metro Engineering

Abstract

In view of the cracking problem of mass concrete caused by excessive amount of cement, concrete for metro engineering was prepared by the cementing material system with a large amount of mineral admixture, and the influence of the different cementing material system and specimen curing age on its durability was systematically studied. The results show that the carbonation depth of concrete specimens increases rapidly in the early stage of carbonation, but slows down in the late stage of carbonation. When the amount of cementing material is the same and the curing age of specimens is 28 days, the amount of cement is the key factor affecting the chloride ion permeability resistance of concrete. After the curing age reaches 84 days, the amount of mineral admixture has a great influence on the chloride ion permeability resistance of concrete. After comprehensive comparison of carbonation resistance and chloride ion erosion resistance of concrete used in metro engineering, it is found that its durability is good, which can meet the durability requirements of major projects with strict service requirements, such as the metro in China.