Experiments and dimensional analysis of contaminated clay soils

An experimental programme was developed to investigate the influence of three viscous-dominant contaminants on the stress-strain response of clay soils. Four degrees of contamination (by weight) - that is, C_c = 2, 4, 6 and 8% - were examined. Natural and contaminated samples were prepared at their respective Proctor optimum condition and further subjected to unconfined compression tests. The dimensional analysis concept was implemented to quantify the stress-strain response. A sensitivity analysis with respect to the proposed dimensional models was also performed to examine the impact of various contamination scenarios on the strength properties. Lubrication at the particle contact level caused by the viscous nature of the contaminant agent portrayed a significant role in describing the stress-strain response. The stress-strain relationship was adversely affected by contamination. Peak strength and stiffness were inversely related to contaminant viscosity μ_c and C_c, with the former representing a more dominant role. An increase in μ_c and/or C_c, however, promoted a notable improvement in the ductility. The predictive capacity of the proposed dimensional models was examined and validated by statistical techniques. The proposed models contain a limited number of fitting parameters, which can be calibrated by minimal experimental effort and hence implemented for predictive purposes.