Investigating the Consolidation and Shear Strength Behavior of Clay Soils Contaminated with Municipal Solid waste leachate

In this research, the effect of leachate on the shear strength parameters of fine soils was investigated in the laboratory conducting 14 consolidation, 42 large-scale direct shear test and SEM photography. Consolidation and shear tests conducted on specimens contaminated with different percentages of leachate ranging from 5% to 20% in short-term after 96 hours of contamination and long-term after 180 days of contamination. The results of these tests indicated that leachate contamination reduced the shear strength and compression index of clay. The peak shear strength of contaminated specimens achieved in lower deformations when compared to intact specimens. In the soil of CH and CL, with the increasing the leachate content up to 20% reduced the shear strength by about 30% in the short-term and by about 40% in the Long-term compared to intact specimens. In the soil of CH, with the increasing the leachate content up to 20%, reduced the compression index of soil by about 45% in compared to intact specimens. Results of this study showed that with the increasing the leachate content up to 20%, the peak shear strength of contaminated specimens achieved in lower deformations (36% lower deformations for CH and 32% lower deformations for CL) when compared to intact specimens.