## 5 Conclusions  
The construction industry must look for a sustainability framework to overcome global resources scarcity and environmental impact by adopting sustainable material management in the concrete manufacturing processes. The proper material management is required to select the siliceous material for the production of concrete product from the ever increasing sources of siliceous materials such as industrial waste products, agro-waste products, building recycled material, natural pozolonic material, and siliceous engineered material. The much needed sustainability may be accrued by considering factors related to technique and the environment as well as socio-economic factors while selecting siliceous concrete materials. Concrete manufacturing, through material management, must adapt to environmental friendly material and processes, which should not only be cost-effective but also provide economic value and safety for society. In the present study, more comprehensive criteria are selected in order to provide sustainability. Moreover, the study adopts twenty sustainability indicators for siliceous concrete materials, thus covering the material management sustainability aspects to a larger extent. It is found from the adopted MCDM approach that among the selected sustainable indicators, the most effective sustainable indicator for managing siliceous materials is concrete material conservation. The least governing sustainable indicator is enhanced employment. It can be concluded from the study that the large scale use of siliceous concrete materials in construction industry will help in the conservation of basic concrete materials and environmental protection, though it will not have direct impact on social development.  
The proposed material management model for siliceous materials suggests that the material could be best utilized for sustainable development by the classifying the various siliceous materials into two groups i.e., Group I with CC \(>\) 0.35 and Group II with CC \(<\) 0.35. The selected siliceous concrete materials, namely, Nano-cement and Nano-particles of siliceous material, Blast Furnace Slag, Fly Ash, and Metakaoline exhibit larger CC value and are hence classified as Group I materials, which possess higher potential of providing sustainability. The siliceous concrete materials of Silica Fume, Waste Glass, Natural Pozolona, Lime Stone, and Rice Husk Ash exhibit lower values of CC, and hence may be regarded as having lower capability towards achieving sustainability in comparison to the Group II. The nano-engineered material, although costly, will prove to be the best material for sustainable concrete construction and development.  
The current research provides just a preliminary framework for the selection of basic materials for concrete construction in alignment with sustainability. In selecting sustainable siliceous concrete materials, this research has opened opportunities for further research in sustainable materials. The results of this study can be further expanded and modified to achieve the ultimate objective of encouraging and improving sustainable construction methods. The present research will be of great importance for the concrete industry dealing with concrete manufacturing and to tackle the challenges like increased manufacturing costs, higher concrete performance requirements, and being risk-free to the environment and society.  
Conceptualization and formal analysis, I.I.F. and M.A.; methodology, software, and validation, J.M., I.LF., M.A., J.M.; writing--original draft preparation, I.I.F. and M.A.; writing--review and editing, J.M.; supervision and project administration, I.I.F., M.A.; funding acquisition, M.A.  
This research was funded by Deanship of Scientific Research King Khalid University, grant number 172 (1440) and the APC was funded by authors.  
The authors thankfully acknowledge the Deanship of Scientific Research for proving administrative and financial support.  
The authors declare no conflict of interest.