The Impact of Bottom Ash and Stone Dust on the 3D Consolidation Behaviour of Soil: An Experimental Analysis

Bottom ash is the waste product that remains after the combustion of coal or other materials in power plants or incinerators. On the other hand, stone dust is a solid waste material produced in the stone-crushing industry and is widely available. Disposing such materials minimizes various geoenvironmental challenges, including landfill disposal issues and health and environmental risks. Waste material (bottom ash and stone dust) management and handling are thus crucial for mitigating such possible risks. The current study aims to use bottom ash and stone dust to improve the 3D consolidation characteristics of clayey-silt with sand soil by mixing different percentages of bottom ash and stone dust into the soil. A laboratory experimental study is executed in a fabricated 3D consolidation apparatus with a circular-shaped footing while drainage is allowed in all directions under a 10 kPa seating load placed on the top of the soil sample to determine the effect of varying waste material percentages mixed with soil on the consolidation behaviour. The investigation results show that the consolidation rate increases with the increase in the percentage of waste material content in the soil, with the highest consolidation rate reaching the addition of 40% waste material. The co-efficient of consolidation increases with the increase in waste material. Also, the settlement of the foundation increases with the increase in waste material content. The present laboratory model is validated with numerical analysis results. The present study is beneficial since it reduces and reuses waste materials to strengthen the weak soil.