Effect of Sulfuric Acid on the Shear Strength and Consolidation Parameters of a Clayey Soil

The vast use of chemical productions and the large amount of leachate which produced by human, lead to the pollution of the soil and groundwater supplies. Acidic contamination is one of the most common contaminations that goes to the nature by different ways such as leachate of factories, industry and acidic rains. These contaminants which cause environmental hazards, are also important in geotechnical perspectives and need more investigations. In this paper, the effects of sulfuric acid contamination on the shear strength and consolidation parameters of a clay soil is studied. Unconfined compression strength and one-dimensional consolidation test conducted on the soil under specific conditions. The soil itself was clean at first, and it was contaminated by adding sulfuric acid in three different pH values (5, 3 and 1). Also in order to compare the test results, one test conducted with drinking water (pH=7.8). The results showed that acidic contamination and pH reduction, decreases the shear strength of clay. Also, by reducing the pH values, the coefficients of compression and swelling increased under the influence of the contaminant. The presence of the acid, increases the coefficient of consolidation and the rate of consolidation.