A Critical Review on Effective use of Chemical Admixture to Reduce Swelling and Shrinkage Characteristics of Soil

Generally, swelling and shrinkage characteristics of the clayey soil is due to volumetric changes that occur in presences of water. Type of minerals present in clayey soil governs the amount of swelling-shrinkage in the soil. The swelling and shrinkage characteristics of the soil is causes minor to major problems to the infrastructure. This problems are reduced in many ways such as sand cushion. CNS layer technique, sand columns, stone columns, vibration technique and by adding chemical admixtures. The chemical additives method is expensive technique, but advantage of this method is that setting time and curing time controlled. This review paper, compares the work of various researchers to reduce swelling-shrinkage using different proportions of chemical admixtures. In this review paper, some chemical salts and chlorides such as calcium carbonate, sodium carbonate, calcium chloride, magnesium chloride and ferric chloride are react with soil and reduced the maximum swelling and shrinkage properties of the soil.