Abstract— In India 22%of the Geographical area is covered by expansive ‘Black Cotton Soil’. These soils are characterized by their highly swelling and shrinkage properties. In dry conditions these soils have high strength which is almost completely lost when they come in contact with water. These soils are having high degree of expansion which creates a lot of problems during the execution of work and after completion of it. Hence stabilization of such soil is prime importance. Attempts have been made to stabilize these soils by using different materials such as lime, cement, asphalt etc. Industrial wastes such as fly ash, furnace slag can also be used for this purpose. In order to improve the engineering and index properties of soil, the experiments have been conducted with industrial wastes of steel foundry called as furnace slag plus black cotton soil. The results show …show more content…
Fraction passing 0.075 mm sieve ranges from 70 - 100 % . The liquid limit and plasticity index values ranges from 40 - 100% and 20 - 60% respectively. Black cotton soils have low shrinkage limit (10 -20%) and high OMC (25 – 30%). All these properties render the soil to be highly sensitive to moisture changes. They are also compressible and plastic in nature. From construction point of view, following are the main problems in case of black cotton soils,
It is very difficult to pulverize the soil as the dry lumps are difficult to break due to dry strength and the wet soil is too sticky and unmanageable. There is excessive variation in volume and stability with variation on water content.
There is considerable shrinkage on drying and resulting in the formation of extensive cracks. Black cotton soils compacted at OMC will also shrink when dried as shrinkage limit is much lower than OMC. The black cotton soils exert high swelling pressures from below on being soaked, causing failure of