The effects of the copper solutions on the short-term and long-term confining properties of a swelling clay

摘要

Waste disposal engineered barriers are often made with compacted swelling clay characterised by high alkaline contents and strong adsorption capacities associated with low permeability. Mass transfer processes as well as pollutant retention ability are relevant clay properties to be studied for the barrier evaluation within both short and long periods of time. In this regard, hydro-chemico-mechanical coupling effects on swelling clay (Foca clay) properties have been studied along soaking paths. Specific oedometer cells were equipped with two liquid injection systems in order to reproduce in laboratory a wide range of domestic waste in situ hydraulic conditions at the waste-clay barrier interface. Both systems were designed to allow, under controlled injection pressure at the clay sample boundary, solute injection using a chosen pollutant in various concentrations; one for solute injection and the other for an air-solute mixture injection.