Stabilization of Clays and Clayey Soils Using Polycom-A Polyacrylamide Additive

The aim of this study is to assess the benefits of using Polycom a polymer-based additive to improve various performance-related properties of clays and clayey soils. Polycom is a commercially available polymer, which has a wide range of applications related to the improvement of various properties of soils. Generally, the substance is used in road construction as a means of stabilizing the soil movement due to changes in moisture content. Studies by the University of Adelaide have indicated that the addition of Polycom to the clay had a significant influence on decreasing the permeability of the respective compacted clay liners (CCL). Three types of soils namely clay of high compressibility and two clayey sand samples are tested in the laboratory by adding Polycom-mixed water. Wet application method is used to stabilize the soils in which the dry Polycom powder is mixed with water that is to be applied to the soil to obtain the optimum moisture content. The Polycom reacts with the water such that a highly viscous solution forms. The effect of Polycom on engineering properties of soils is investigated by dry density vs moisture relationship, unconfined compressive strength (UCS), and direct shear tests. Results show that clay of high compressibility (CH) showed appreciable improvement in strength in terms of UCS with the stabilizer for different curing periods. The improvement in UCS is about 160% with respect to strength of untreated soil. Similarly for clayey sand (SC), the increase is about 150% and 40% in cohesion and angle of internal friction, respectively, for 5 days of curing with respect to untreated soil strength.