**8. Practical Applications of Granite Dust**

An embankment was constructed in Korea using locally available silty material and granite dust sourced from two different quarry sites (biotite granite quarry from Yangju, Gyeonggi province; granitic gneiss from Gongju, South Chung cheong province) [45]. The granite dust is added in multiples of 25% from 0 to 100 and its response to enhancement in targeted geotechnical properties was determined. This case study revealed the fact that, an embankment of silty material stabilized with granite dust should attain a gradient of 1:1.8 for 10 m height and 1:1.5 for 15 m height in order to satisfy the stability analysis as per Korean standards. Up on inclusion of granite dust, the specific gravity of the mix increased whereas the MDD and shear strength of the mix decreased as seen from Table 9.

**Table 9.** Effect of granite dust on the shear parameters of a local silty soil (Modified after [45]).


In Jimma town of Ginjo kebele, Ethiopia, an expansive soil (clayey soil) at subgrade level was stabilized using granite dust [57]. The dosage of granite dust was limited to 50% (added in increments of 5%). CBR requirements for subgrade were met at 30% to 35% of granite dust addition as seen in Figure 10. The thickness of the subgrade was found to reduce by 20.6% compared to an untreated case. Their study concluded that clay-granite dust soil satisfies the requirements for subgrade layer [57].

**Figure 10.** Improvement in the CBR of subgrade soil with addition of granite dust (Modified after [57]).

#### **9. Conclusions**

The current review article dealt with the generation of granite dust and shed light on its influence on the engineering properties of soils exhibiting different mineralogy. The workability of granite dust amended soils in the presence of an additional stabilizer is critically reviewed. The performance of granite dust as a backfill and a pavement material is discussed. The mechanism behind the improvement of each soil engineering property with granite dust addition is explained. The major outcomes of this review article are:


Granite dust is a sustainable and remarkable material exhibiting relatively low embodied energy levels. For a given scenario, when granite dust is amended with native soil, the amount of CO2 released due to granite dust addition is compensated by the reduced use of locally available materials. Accordingly, granite dust addition results in reduced carbon footprint values, and this treatment strategy is close to carbon neutral.

Proposed Research Gaps

• To explore the particle size effect of granite dust on the strength characteristics of the soil.


**Author Contributions:** Conceptualization, G.A. and A.A.B.M.; methodology, G.A. and A.A.B.M.; formal analysis, G.A.; A.A.B.M. and A.A.; resources, A.A.B.M. and A.A.; data curation, G.A. and A.A.B.M.; writing—original draft preparation, G.A., A.A.B.M. and A.A.; writing—review and editing, A.A.B.M. and A.A.; visualization, G.A. and A.A.B.M.; supervision, A.A.B.M.; project administration, A.A.B.M. and A.A.; funding acquisition, A.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** College of Engineering Research Center and Deanship of Scientific Research at King Saud University in Riyadh, Saudi Arabia.

**Data Availability Statement:** The content presented here is sourced from existing published literature. Hence, this clause doesn't arise.

**Acknowledgments:** The authors acknowledge the College of Engineering Research Center and Deanship of Scientific Research at King Saud University in Riyadh, Saudi Arabia, for their financial support for the research work reported in this article. The authors thank the reviewers for their constructive comments which helped the cause of the manuscript.

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

#### **References**

