Brick Kiln Dust Waste Management Through Soil Stabilization

Abstract

The increase in population and its industrial activities have pushed the quantities of waste generation to an all-time high. There is an urgent need for sustainable waste management by developing design methodologies for their utilization in the construction industry. This study focuses on the geotechnical and environmental aspects of utilizing brick kiln dust (a waste product from brick kilns) in stabilizing the subgrade layer of flexible pavements accompanied with a simultaneous reduction in the associated greenhouse gas emissions. In order to achieve wide applicability of this waste, the proposed stabilization was performed on six subgrade soils of varying plasticity, ranging from the clay of intermediate plasticity to sand with an appreciable amount of silt. Soil-brick kiln dust mixes prepared with 10%, 20%, 30% and 40% contents of brick kiln dust were subjected to experimental investigations. Their compaction and strength characteristics were determined by performing Proctor (modified) tests and California bearing ratio (CBR) value respectively. The greenhouse gas emissions were calculated on the basis of standard inventories of carbon coefficients for road construction materials. The results indicated that the CBR, a key strength parameter of soil was significantly improved with the use of brick kiln dust. The improvement in the CBR was directly proportional to the plasticity of soil. The brick kiln dust stabilization significantly reduced the pavement layer thicknesses as also the associated greenhouse gas emissions for all the soils. The results obtained are indicative of the potential use of brick kiln dust in building sustainable and durable pavements with reduced global warming potential.