A final Project Submitted to Institute of Technology Department of Civil Engineering School of Graduate Studies, Arba Minch University, In partial fulfillment of the requirement for the Degree of Masteries of Science in Geotechnical Engineering.

Abstract

Expansive soil is generally a result of geological history, sedimentation and local climatic conditions Arid climatic conditions and severe weathering environment prevailing in north eastern part of Africa promote the widespread occurrence of expansive soils in this region In Ethiopia, covering nearly 40% surface area of the country expansive soils are observed in area such as central Ethiopia. In this project Expansive soil mainly found around hosanna town has been assessed. To do this different literature is reviewed and Index properties and swelling pressure prediction on 8 disturbed 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. The new formulas are developed, by taking one or more of the soil property parameters (Liquid limit, plastic limit, moisture content, dry density and plastic index) in different combinations. To develop the equations, 8 test results are used as an input data for SPSS 15 windows software. The best equation is proposed, and conclusions and recommendations are made. Lastly, future works are suggested.