Improvement of mechanical properties of recycled aggregate concrete basing on a new combination method between recycled aggregate and natural aggregate

•The new combination method between RA and NA in RAC is developed.•New combination method improves significantly the mechanical properties of RAC.•Using new method, the amount of recycled concrete aggregate in concrete can raise up 50%.•The mechanical properties of RAC are affected by RA content following both new and conventional combination methods.

This paper present a new methodology of combination between recycled concrete aggregate (RA) and natural aggregate (NA) in concrete for the purposes of improving the quality of recycled aggregate concrete (RAC) and increasing the amount of RA in RAC. This study investigated mechanical properties of RAC by using new methodology and conventional methodology at different replacement percentages of RA. New methodology enhanced significantly mechanical properties of RAC comparing to conventional method. Using new method for RAC, the amount of RA can be raised up to 50% in concrete while conventional method limited the amount of RA should be less than 30%.