The Characteristics of Collapsing Soil in Marshes Area


The soils of the marshes in the south of Iraq are considered as soft soil, which is usually a silty clay and clayey silt. In this study, compressibility and shear strength characteristics are studied for three soils used in this work, were brought from three different areas (Alchebaish, Alhalfaiya and Almejar Alkabeer) near marshes and taken at depth ranging from (1-1.5) m below ground level after excavating the upper soil strata. All fundamental tests were performed on these soils. Laboratory tests results showed that these soils have high collapsibility and that shear strength parameters of c and ) decrease when soaked in water but the main decrease was in (c) value. Also the study includes the influence of the initial void ratio and the water content on the modules of the collapsibility. The value of collapse Potential seems to depend mainly on the natural water content and initial void ratio. The collapse potential increases with the increase of void ratio and decreases with increase of water content.