Combined Effect of Marble Dust and Waste Paper Sludge in Improving Engineering Properties of Black-cotton Soil of Gelan Area, Ethiopia

Black-cotton soil creates a problem in construction sites of Gelan area, Ethiopia because of its swell and shrinks behavior due to moisture change. In the present study, an alternative method of soil stabilization using the combined effects of Marble dust and waste paper sludge is investigated based on laboratory test results. Standard compaction and unconfined compressive strength tests were performed by mixing Black-cotton soil with waste paper sludge of 5, 10 and 15% by mass of soil. From the tests and experimental studies, addition of 5% waste paper sludge is obtained as optimum blend to improve soil strength. Therefore, soil is mixed with varying percentages of marble dust (i.e., 10, 20, 30 and 40%) in addition to 5% waste paper sludge which resulted in significant improvement of the soil plasticity, swelling and strength characteristics. From the study it is concluded that addition of 5% waste paper sludge with 30% marble dust is the optimum amount to improve the engineering properties of the Black-cotton soil.