Soil stabilization by chemical additives

The effects of phosphoric acid and lime additives on the compaction characteristics, the cohesion value, and the angle of friction of soils containing various percentages of Kaolin clay were compared and the applicability of Sherif's procedure for determining the coefficient of lateral earth pressure at rest for chemically stabilized soils was investigated. Both additives were found to increase the cohesion and the angle of friction of compacted sandkaolin clay mixtures. Increments were greater in basic addition than in acidic addition. The increment in the cohesion value is dependent mostly on clay content, water content and dry density while the increment in the angle of friction is mostly dependent on clay content and water content, with the factors of the type and content of the chemical common to both increments. Compaction data indicate that maximum dry density, and optimum water content are dependent on clay content and chemical type and content. The expression proposed by Sherif was found to be applicable for chemically treated cohesive soils.