Effect of density and surcharge pressure on collapse potential of loess soil treated with bagasse ash

Massive structures constructed on loess soil are prone to failure owing to sudden alterations in the soil-structure dynamics upon flooding. Utilizing industrial waste, such as bagasse ash (BA), offers a potential solution to address this issue. In the scope of this investigation, both undisturbed and disturbed soil samples were procured from the arid region of District Muzaffargarh in Punjab, Pakistan. BA was incorporated at a concentration of up to 8% to enhance the performance of the loess soil, with a curing period of 7 days. To determine the influence of BA, density variations, and surcharge pressure on collapsible potential, specimens were reconstituted at natural density, standard Proctor dry density, and modified Proctor dry density, in conjunction with corresponding natural and optimal water content. Exponential mitigation of collapse behavior in the treated soil is observed with an increase in density, surcharge pressure, and BA content. Additionally, to compare microstructural characteristics, analyses involving scanning electron microscope (SEM) was conducted on both untreated and treated samples. The incorporation of BS is reflected in SEM results, revealing establishment of bonds (due to formation of cementitious gel) among soil particles, attributed to hydration and pozzolanic reactions. SEM analyses also elucidate the transformation of the dispersed and silt-dominated structure of the native loess soil into a reticulated structure without of micro-pores, attributed to the incorporation of BA.