Variation of experimental results of oedometer testing due to the changes of pore fluid

摘要

Clay soils as a base liner of industrial and municipal waste deposit are exposed to intensive physico-chemical attacks by leachates of wastes. Existence of heavy metals in the leachates of waste changes the pore fluid characteristics and influences on the double layer properties of clay particles. The application of clay soils in any landfill liners or slurry walls requires knowledge of the variation and changes of their mechanical behaviour in terms of consistency, strength and compressibility. This process may cause a noticeable change in the mechanical behaviour of clays that depends strongly on physico-chemical properties of pore fluid. This study is aimed to conduct an investigation of the mechanical behaviour properties especially volume changes behavior and consolidation characteristics of bentonite during the existence of heavy metals in pore fluid. In this paper, the compressibility behaviour of bentonite during interaction with lead and zinc, with different concentrations is evaluated. The compressibility performance includes, the evaluation of consolidation coefficient (C_v), compressibility index (C_c), permeability coefficient (K_v), and void ratio-effective stress (e-log p) variation.