Expansive soil and bedrock underlie more than one third of worldâ€˜s land surface. It is recorded in other countries that each year, damage to buildings, roads, pipelines, and other structures by Expansive soils is much higher than damage that are caused by floods, hurricanes, tornadoes, and earthquakes combined. Such damages occur when the pressure exerted by the soil is greater than the foundation pressure. Consequently assessing the swelling pressure is an important step in designing structures on Expansive soil.rnIn this thesis Expansive soil mainly found in Dukem town has been assessed. To do this different literature is reviewed and Index properties and swelling pressure tests on 24 disturbed and 18 undisturbed samples were conducted. Based on the index property test results and different classification systems, the study area soil types are identified. Moreover, the validity to our condition of empirical expressions that relate the swelling pressure to the index and physical properties, developed by several researchers is checked and new equations are developed.rnThe new formulas are developed, by taking one or more of the soil property parameters (Liquid limit, plastic limit, shrinkage limit, moisture content, dry density and plastic index) in different combinations. To develop the equations, 15 test results are used as an input data for SPSS 15 windows software. The equations are then tested for three control samples. The best equation is proposed, and conclusions and recommendations are made. Lastly, future works are suggested