International Journal of Advance Science and Technology Vol. 29 No. 10S, (2020), pp. 750-757 750 ISSN: 2005-4238 IJAST Copyright ⓒ 2020 SERSC Engineering Properties of Clayey Soil Stabilized with Waste Granite Dust Ahmed Salama Eltwati *1 , Fares Tarhuni 2 , Alaa Elkaseh 3 *1 Assistant Professor, Department of Road and Airport Engineering, Bright Star University, Brega, 12345, Libya 2 Department of Civil Eng., High Institute for Engineering Profession, Benghazi, 12345, Libya 3 School of Civil Engineering, Universiti Teknologi Malaysia, Johor Bahru, Johor, 81310, Malaysia 1* Ahmed.Eltwati@bsu.edu.ly, 2 st257@gmail.com, 3 alaaelkaseh@gmail.com, Abstract The properties of soil play a major effect on the design of road pavements. Thus, using waste materials to develop the characteristics of weak soil is being progressively necessary for industrial constructions. In past years, several pieces of research have been done to show the significance of these waste materials on the strength of the soil. This research aims to focus on the impact of granite powder on the behavior of the soil subjected to loading. Therefore, soils blended with several amounts of granite powder i.e. 4%, 8%, 12%, 16%, and 20% of the total weight were examined. The CBR, compaction and direct shear tests were executed to evaluate the performance of the untreated and treated soils. The findings proved that adding granite dust increased noticeably the shear strength, CBR and dry density of the soils. It was found that an addition of 8% granite dust to the natural soil yields the most appropriate results among other contents of granite dust. Hence, it is concluded that the granite dust has good potential to be used as an additive for improving the engineering properties of clayey soil. Keywords: Granite dust; Subgrade; CBR; Waste materials, Dry density 1. Introduction The design of flexible pavements depends greatly on the strength of the soil (Katte, Mfoyet, Manefouet, Wouatong, & Bezeng, 2019; Minhans, 2011; Patel, Kumar, & Sharma, 2019). The traffic loading is conveyed to the lower layer of the subgrade throughout the pavement structure. In the preparation of subgrade for road construction, utilizing wide-ranging choices of conventional materials are, commonly, inevitable due to economic and natural considerations (Ben-Edigbe, Abdelgalil, & Abbaszadehfallah, 2012; Hastuty & Rahman, 2019; Phanikumar, m, & e, 2020). Thus, treating poor soil is essential in highway bedding construction (Das & Ghosh, 2020). Alternating the poor soil is one of the traditional options (Abdelgalil & Nor, 2014b; Assefa, 2016). However, it is high-priced and impractical in highway projects due to the considerable efforts required (Abdelgalil & Nor, 2014a; Ghorbani & Hasanzadehshooiili, 2018; Mousavi & Karamvand, 2017). Therefore, blending the poor soft soil with a modifier has become a necessity. Enhancement of soft subgrade by applying lime, Portland cement, and diverse synthetic mixes is an effective method (Rehman & Moghal, 2018). On the other hand, consuming these additives could raise the total cost (Ahmed Salama Eltwati, Hossein, & Nasr, 2020; Patel et al., 2019). However, using industrial by-products in the enhancement of poor soil is common as it preserves the environment and reduces the expense (Mina, Kusuma, & Ulfah, 2019; Shukla, Tiwari, Rajbhar, & Mittal, 2019). Crushing rock dust is one of the waste substances (Assefa, 2016; Mishra & Arora, 2019). The granite dust is formed from the cutting and polishing of granite stone (Jain & Jha, 2020). The amount of granite slurry waste generated every year is about 3