The Effect of Additives on Clay Soil Properties Using Cement and Lime

Iran is a country with large clay resources in most of its provinces. The problems associated with these soils arise out of a variety of parameters that result in variable behaviors in these soils. Different lines of research are required to deal with each type of behavior. A lack of understanding of clay soils and their minerals may result in adverse consequences. When a structure is built upon clay soils, such events as pipe bursts, water penetration and groundwater uplift may cause cracks and subsidence in the foundation of the structure following the soil shriveling so that this type of soil is categorized as problematic. Basically, a soil is considered problematic when it behaves unexpectedly under specific circumstances so that this unexpected behavior often brings about problems. That is why these soils are deemed problematic. It seems, therefore, necessary to identify and classify these soils and take measures to modify their swelling and shrinkage properties. In the present study, cement and lime were used as two chemical additives to improve swelling and shrinkage properties in expansive soils in Golestan province. To this end, we selected four soil types with plasticity indices 25, 30, 35 and 40. Then the plasticity properties of the soils including liquid, plasticity and shrinkage limits as well as plasticity index were investigated and compared among the specimens in different mixture proportions.