Characterisation of recycled concrete aggregates when used in asphalt concrete: a technical literature review

Abstract

Concrete is one of the most widely used construction and building materials. When a concrete structure reaches the end of its life, the demolition waste may be used to produce recycled concrete aggregates (RCA). RCA mainly differ from natural aggregates in the attached mortar that remains onto the RCA surface. The differences between the properties of RCA and those of natural aggregates will condition the performance of the construction materials that contain RCA. Specifically, asphalt concrete (AC) that contains RCA has many technical disadvantages due to the porous nature of the attached mortar and thus, the high water and bitumen absorption and the low resistance to fragmentation of the RCA. However, some authors have experimented with the application of treatments to the RCA that allow its successful use in the manufacture of AC, which contributes to sustainable development. This paper reviews the main properties of the RCA, particularly when used to produce AC.

Keywords:

• recycled concrete aggregates
• porous attached mortar
• mechanical properties
• physical properties
• asphalt concrete

Acknowledgements

The authors wish to acknowledge the Spanish Ministry of Education and Science for sponsoring this research through Project BIA2010-17751.