Feasibility and performance analysis of carbonated recycled aggregate concrete

The main aim of this paper is to improve the quality of recycled coarse concrete aggregates by using the carbonation technique. The aggregates are tested for physical properties and microstructural analysis. The concrete produced using these treated aggregates is tested for Non-destructive, Mechanical and Durability properties and the results are compared for control concrete, recycled aggregate concrete, and carbonated recycled aggregate concrete. A total of three mix combinations named NAC (using 100% natural coarse aggregate), RAC (using 100% recycled coarse aggregate) and CRAC (using 100% carbonated recycled coarse aggregate) were prepared using w/c ratio of 0.48. It has been found that by using the carbonated recycled concrete aggregates (CRCA), RAC's non-destructive, mechanical and durability properties can be improved because of the method of carbonation. The compressive strength of the 100% RAC shows a decrement of 24.52% as compared to the 100% NAC. Whereas the compressive strength of the 100% CRAC shows an increase of 21.05% as compared to the 100% RAC, but it shows a decrement of 8.63% as compared to the 100% NAC. It not only refines the properties of RCA but also reduces the greenhouse effect which is originated by CO2 emissions.