The need for sustainable construction practices has led to an increase in interest in using recycled concrete aggregate (RCA) as a feasible substitute for traditional aggregates. This approach aims to tackle environmental issues and decrease the dependence on virgin materials in the production of concrete. This paper investigates the potential of using RCA in concrete for structural concrete elements of 100 years design life. The study focuses on evaluating the mechanical properties and durability performance of concrete mixes, together with the use of 50% fly ash and/or slag. This paper provides insights into the performance of recycled concrete through comprehensive laboratory testing, including analyses of compressive strength, drying shrinkage, and volume of permeable voids (VPV). Durability performance, such as carbonation resistance, chloride diffusion coefficient and surface resistivity have been measured. This research provides valuable information to support informed decision-making for stakeholders in the construction industry who look to adopt more environmentally friendly practices.