Structure-based hydro-mechanical properties of sand-bentonite composites

In this contribution, the hydro-mechanical behaviour of saturated and unsaturated sand-bentonite soil is investigated in the context of the recently developed Concept of Double Porosity (CDP). The geomaterial under study is assumed to consist of an incompressible, rigid, elastic solid skeleton surrounded by viscous water and gas fluids, and connected via a network of elastoplastic clayey bridge/buttress units. Roundness and sorting are varied for the sand constituent. The clay fraction (CF) is also varied across testing specimens. The experimental work here introduces two micromechanical models (small clay and large clay) which facilitates interpretation of macro-scale coupled hydromechanical behaviour of composite sand-bentonite geomaterials. The findings from this work will aid design practitioners through a tentative decision support system proposed in closing remarks.