**12. Conclusions**

Reclaimed destroyed concrete has a significant potential for value-added applications to maximize environmental and economic benefits. Significant savings can be achieved by making RCA a valuable resource in the new generation of concrete. In the current study, a critical analysis of a recycled concrete aggregate for the production of heavy-duty concrete structures was carried out. The following conclusions were drawn from this article:


The following are the summaries of recommendations:

1. The idea of using existing production facilities to produce recycled concrete aggregate is misplaced as the construction manager may initiate excessive additional costs as a result of the specific conditions of the halls. Nanotechnology can be used to advance RCA manufacturing because of its enormous potential to improve production and quality in high-efficiency apprenticeship manufacturing. In addition, the use of nanotechnology is aimed at changing the operating mode in construction using nanomaterials. The examination describes several properties of RCA at the nanoscale using a variety of state of the art equipment. Therefore, it is worth focusing on nanosciences, which is critical when investigating the microstructure of RCA. In addition, the strength characteristics of RCA can be improved through the use of nanomaterials to obtain greater strength than conventional concretes.


**Author Contributions:** Conceptualization, N.M., R.F. and M.A.; methodology, N.M., R.F., M.A. and A.M.Z.; validation, N.M., R.F., M.A., A.M.Z., G.M., N.V., S.K., T.O. and Y.V.; resources, N.M., R.F., M.A., A.M.Z., G.M., N.V., S.K., T.O. and Y.V.; data curation, N.M., R.F., M.A., A.M.Z., G.M., N.V., S.K., T.O. and Y.V.; writing—original draft preparation, N.M., R.F., M.A. and A.M.Z.; writing-review and editing, N.M., R.F., M.A., A.M.Z., G.M., N.V., S.K., T.O. and Y.V.; supervision, M.A. and R.F.; project administration, R.F., M.A. and N.V.; funding acquisition, M.A., N.V., S.K. and Y.V. All authors have read and agreed to the published version of the manuscript.

**Funding:** No fund available.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data sharing not applicable.

**Acknowledgments:** The authors gratefully acknowledge the support given by Deanship of Scientific Research at Prince Sattam bin Abdulaziz University, Alkharj, Saudi Arabia; Moscow Automobile and Road Construction University, Moscow, Russia; and the Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Yemen, for this research.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

