Sailie, E. Louis2019-09-172020-01-072019-09-172020-01-071980Sailie, E. L (1980) Swelling, strength and consolidation characteristics of tropical black clays (Black cotton Soils), Masters dissertation, University of Dar es Salaam. Available at (http://41.86.178.3/internetserver3.1.2/detail.aspx)http://localhost:8080/xmlui/handle/123456789/484Available in print formTropical black clays, also known as black cotton soils, are high volume change soils in which montmorillonite is the principal clay mineral. These soils cause tremendous damage to structures and, in this country, they are undoubtedly the most problematic in civil engineering constructions. In the present research work, an attempt has been made, through careful laboratory experimentation, to establish swelling, strength and consolidation characteristics of black cotton soils in Tanzania; factors influencing them and their relations to significant index properties. The laboratory studies have shown that most black cotton soils are highly expansive, posses low shear strength both at the peak and residual values and are of poor consolidation properties. It has been established that these characteristics are mainly influenced by the potential volume change (type and amount of clay minerals present) and the physical state of the soil. The index of plasticity and the dry density have been found to be the most useful indices for evaluating black cotton soils. Design considerations for the use of black cotton soils both as foundation and construction materials have been presented and discussed.enBlack cotton soilBlack claystropicalDye industryDye plantsTanzaniaThesis