Sustainable Materials: A Review of Recycled Concrete Aggregate Utilization as Pavement Material

Abstract

In this paper, a comprehensive literature review was conducted on the utilization of recycled concrete aggregate (RCA), which is the dominant construction and demolition waste material, in base and subbase layers and its comparison with natural aggregate (NA). The effects of crushing on the particles as a result of the compaction on the resilient modulus, permanent deformation, and California Bearing Ratio are analyzed. The paper also contains the NA consumption and waste disposal policies of different countries, RCA standards, and the environmental-economic reasons for its use. This literature review mainly focuses on pavement layers as this is the main application of RCA in the use of recycled materials. Developing integrated construction and demolition waste management will help achieve the primary goal of preventing and reducing the generation of these wastes, both locally and globally. In this way, not only is the main purpose of preventing the increase in the production of construction and demolition waste achieved, but also the reuse and recycling of the waste materials produced are encouraged. Results show that RCA has equivalent or better performance than virgin aggregate for almost any application with proper care and process control, and can be used in unbound pavement layers or other applications requiring compaction. But it is always recommended that its mechanical properties and durability performance be evaluated with full-scale tests before use. The information provided will be useful for contractors and engineers to evaluate alternative solutions and to explore the rational use of such sustainable materials in applications.