Durable performance of recycled aggregate concrete in aggressive environments

Abstract

Recycled aggregate concrete is an eco-friendly material that is increasingly being used in new constructions. Nowadays, this application is mainly limited by user’s lack of confidence, as coarse recycled aggregate (CRA) is usually more porous, i.e., it has a higher water absorption, than coarse natural aggregate. This difference is a primary concern for practitioners when they have to comply with durability requirements. Although some uncertainties remain in this regard, significant progress has been made in the last few years concerning the assessment of durable recycled aggregate concrete. This paper reviews this topic and includes aspects related to chloride penetration, sulfate attack, freezing and thawing, high temperature, and alkali-silica reaction. Generally, although there are some particularities related to each type of attack, the high porosity of CRA is compensated by other features, such as different texture, increased mechanical compatibility with the matrix, or content of hydration products. Experimental results in the literature show that there are no reasons to consider that durable, sustainable structures cannot be built with recycled aggregate concrete.