Stress-strain Behaviour of Residual Soil Mixed with Granite Dust

Soil stabilization is a widely adopted technique to improve the geotechnical properties of problematic soils, traditionally achieved using calcium-based materials such as cement, lime, and fly ash. However, these conventional additives contribute to carbon emissions, prompting interest in alternative industrial by-products like granite dust. This study explores the effectiveness of granite dust as a stabilizer for enhancing the stress-strain behavior of residual soils. Residual soil samples were collected and mixed with varying percentages of granite dust at 0, 2, 4, 6, 8 and 10% and tested using unconfined compressive strength (UCT). The specimens were tested with curing time of 7 days and compared to without curing time. Results indicate that the addition of granite dust improves soil strength, with 8% of granite dust yielding the highest peak deviator stress of 690 kPa after 7 days of air curing with minimal axial strain (5.2 mm). While higher granite dust content, such as 10%, showed initial strength improvement without curing, it experienced diminishing returns after curing. The study concludes that 8% granite dust is the optimal content for enhancing the mechanical properties of residual soils, providing an eco-friendly and effective alternative to traditional soil stabilization methods.