EFFECT OF MARBLE DUST ON INDEX PROPERTIES OF BLACK COTTON SOIL

This paper presents the results of a laboratory study undertaken to investigate the effect of marble dust powder on the index properties of black-cotton soil. The black-cotton soil has a poor supporting capacity and large change in volume on variations of moisture content. Such expansive soils may need to be improved to make them suitable for construction activities. The objective of study is to evaluate the feasibility of industrial waste like marble dust as soil stabilization material. To investigate the effect of marble dust on index properties of black-cotton soil a series of laboratory experiments have been conducted on black-cotton soil samples mixed with 0 % to 40 % of marble dust by weight of dry soil. The test results showed a significant change in consistency limits of samples containing marble dust. The liquid limit would decrease from 57.67 % to 33.9%. The plasticity index decreased from 28.35 % to 16.67 % and shrinkage limit increased from 8.06 % to 18.39 % with the addition of marble dust from 10 % to 40 % of the dry weight of the black-cotton soil. Also the differential free swell decreased from 66.6 % to 20.0%, showing appreciable decrease in swelling behaviour. From this laboratory investigation it is concluded that the waste material like marble dust generated from stone industries has a potential to modify the characteristics of expansive clay like black-cotton soil. There is significant improvement in the index properties of the black-cotton soil on addition of marble dust into it. The expansive behaviour of the clay has reduced to a great extent