Sustainable reuse of ceramic waste powder as a supplementary cementitious material in recycled aggregate concrete: Mechanical properties, durability and microstructure assessment

Waste concrete as one of construction and demolition wastes is generally collected for the production of recycled coarse aggregate (RCA) to alleviate environmental issues. However, the poor physical performances of RCA limit its application in concrete. Thanks to the rich silica-alumina contents and large reserves in China, the ceramic waste powder (CWP) is promising to be used as an effective supplementary cementitious material (SCM) in cement-based materials. This study reports the development of recycled aggregate concrete (RAC) using CWP as a partial replacement of Portland cement. The mechanical properties, sorptivity, rapid chloride ion penetrability, microstructure, ecological evaluations of RAC containing CWP are determined. The experimental results demonstrate that the eco-friendly RAC incorporated CWP has sufficiently high strength and its compressive strength at 56d is 36.01 MPa. In terms of penetrability behaviors, the rapid chloride penetrability and sorptivity of RAC decrease when the 60% RCA and the 10% CWP are utilized simultaneously. Furthermore, the incorporation of CWP significantly reduces the cost, thermal energy consumption and carbon dioxide emission of concrete. Based on the findings, the applications of CWP in generating a durable eco-friendly construction product are appealing as it not only provides an alternative approach to reuse the wastes, but also achieves superior performance.