Improving the Properties of Black Cotton Soil using Aluminium Cans

Abstract

Black cotton (BC) soil is a problematic soil, as it is expansive in nature. The swelling and shrinking characteristics in Black Cotton (BC) soil is imparted due to the presence of the mineral component montmorillonite. It is predominantly clay, black in colour with a smooth texture. Construction over this particular soil type is always challenging due to its low strength and less drainage property. This soil type is always a threat to the strength and stability of pavements and highways. Beverage cans are globally produced in huge amount. Aluminium cans are the largest source of aluminium in the waste stream. Also, recycling of aluminium continuously affects its quality. This study was an attempt to improve the shear strength characteristics of black cotton soil by using strips of waste aluminium cans as reinforcement. It is a cost effective and eco-friendly attempt. The usage of aluminium fibre increases the tensile strength of soil thereby improving its properties as a subgrade. Cans were cut into 3mm thick strips and were added to soil in 2, 4, 6 and 8% by dry weight. The compaction test, unconfined compression test, CBR test and free swell test were conducted on the aluminium strips reinforced soil. The results obtained from the study showed a significant enhancement in the soil properties such as maximum dry density, shear strength and CBR value.