INFLUENCE OF THE PROPERTIES OF PORE-FLUID RICH IN HEAVY METAL ON ERRORS ASSOCIATED WITH CONSOLIDATION AND ATTERBERG LIMIT EXPERIMENTS

It is known that engineering judgment and design are signicantly a function of experimental results. Due to the importance of the experimental results of geotechnical and geo-environmental engineering projects, determination of the reliability of these experiments is an important factor in the acceptance of experimental investigation. The error associated with these experiments directly in uences the reliability of test results. In spite of the importance of determining errors associated with soil mechanics tests, there has been very limited research towards addressing this subject. In addition, most prior research has focused on distilled water as the pore uid of the soil. Furthermore, no prior research has addressed the in uence of heavy metals on the extent of experimental error in soil mechanics experiments. The main objective of this research is to determine the impact of electrolyte properties of soil on the reliability of results of consolidation and Atterberg limit tests. To achieve this objective, a series of consolidation and Atterberg limit experiments, with tens of replicate samples, was performed. In these experiments, bentonite was mixed with dierent concentrations of heavy metal (lead nitrate). Then, the coecient of variation of the results was calculated. The results show that the change in the pore uid properties of soil causes a change in the properties of the soil double layer, which, consequently, aects the error associated with these experiments. For instance, a 30% to 85% change in the COV of the Atterberg limit test and a 4% to 70% change in the COV of the consolidation test were observed once the pore uid properties of the soil are changed. Finally, it is concluded that the presence of contaminant in dierent concentrations might increase or decrease experimental error. The results of this research can be used to determine the required replicate samples to achieve specic reliability in consolidation and Atterberg limit tests.