Impacts of heating and surfactant treatments on the geotechnical properties of a cohesive soil

An experimental investigation was performed to assess the effect of heating and surfactant on treatment of a soil contaminated with gasoline. Contaminated soil samples were prepared by adding 5, 10 and 15% weight of gasoline to a cohesive soil. The contaminated soil samples were treated by applying heating at 50, 100 and 150 °C. In addition, treatment of the contaminated samples was done by using two different types of surfactant, namely SDS (Sodium Dodecyl Sulfate) and Tween 80. The physical and mechanical properties of the natural soil, contaminated soil and treated soil were determined through experimental tests including Atterberg limit, grain size distribution, compaction and unconfined compression tests. Comparison of the results showed that adding gasoline to soil changes its behavior and the amount of change was function of percent of gasoline. The results also indicated that heating can be used for treatment of the contaminated soil. Comparison of the results showed that using surfactant was more effective in treating the contaminated soil than thermal treatment and the properties of surfactant-treated soil were closer to the original condition. The results also showed that SDS surfactant was more effective in treating the contaminated soil than Tween 80.