Severe acid rain simulation using geotechnical experimental tests with mathematical modeling

Severe acid rains can be a major source for geotechnical and environmental problems in any soil depending on the acid type and concentration. Hence, this study investigates the individual severe effects of sulfuric, hydrochloric and nitric acids on the geotechnical properties of real field soil through a series of experimental laboratory tests. The laboratory program consists of experimental tests such as consistency, compaction, unconfined compression, pH determination, electrical conductivity, total dissolved salts, total suspended solids, gypsum and carbonates contents. The experimental tests have been performed on the untreated soil and individual acid treated soil for acid concentrations range of 0% to 20% by weight. In addition, a unique hyperbolic mathematical model has been used to predict significant geotechnical characteristics for acid treated soil. The plastic and liquid limits and optimum moisture content have been increased under the effect of all the used acids whereas the maximum dry density and unconfined stress-strain behavior have been decreased with increasing the acid concentrations. Moreover, the used hyperbolic mathematical model has predicted all the geotechnical characteristics very well with a very high coefficient of determination (R2) value and lowest root mean square error (RMSE) estimate.