Permeability prediction of soils including degree of compaction and microstructure

The present paper deals with the proposition of an original analytical permeability model of compacted soils. The model involvesthe microstructure of the material through the porosity and the pore-size distribution obtained by mercury intrusion porosimetry (MIP), as wellas the degree of compaction. Their effects on the morphological parameters of the porous network (tortuosity and interconnection of pore network)are studied. The model was developed and tested on various types of soil: a loamy sand, a gravelous sand, a clay, and an alterite. Sampleswere compacted with various degrees of compaction: 85, 95, 100, and 105% of the optimum dry density as determined by a standard compactionmethod. The experimental results obtained for both loamy and gravelous sands and for clay were well reproduced by the model, except forthe alterite. Such resultsmight be explained by the high brittleness of the alterite, leading to a crumbling phenomenon rather than to its densificationduring the compaction process