In this very research, an experiment related to a structural property of matter by using a concrete mix with fly-ash, which is an industrial by-product, and a high-quality recycled aggregate defined by the KS F2573 (recycled aggregate for concrete) that is produced through a high class treatment method in order to carry out a technical verification such as a long term durability and a change in the solidity level according to the recycled aggregate replacement ratio. In addition, for the compressive strength and the estimation of flaws which are the main indexes for evaluating concrete quality, the utilization of the non-destructive test is continuously increasing. Among the non-destructive tests, the ultrasonic pulse velocity test and the rebound hardness test is utilized to compare and analyze the correlation between the natural aggregate concrete and the wave velocity of recycled aggregate concrete as well as the value of rebound hardness in order to provide a credible data, to further furnish a fundamental data for the maintenance and management of a structure made of high-quality recycled aggregate. By doing so, this very research will allow for an improvement in awareness as well as an increase in the application of recycled aggregates.