Volume change behavior of Argentinean collapsible loess inundated by organic liquids.

FRANCISCA, FRANCO M.; GIOMI IGNACIO; MARCOS ALEXIS MONTORO

Sydney

Congreso; 20th International Conference of Soil Mechanics and Geotechnical Engineering,; 2022

International Society of Soil Mechanics and Geotechnical Engineering

Argentinean loess has volume change properties that are highly dependent on moisture content. Typical loess are composedby fine sand and silt particles jointed by clay bridges and precipitated salts that form macro-pores which may undergo high volumedecreases due to load or moisture content increases. Collapse of loess structure is a well-known mechanism that has been studied bymany authors in the past. However, there are only few studies related with volume changes produced by the contamination with non-polarorganic liquids (NAPL). Presence of NAPL is a frequent scenario due to accidental oil spills during fuel transportation and storage. Thisresearch presents an experimental analysis on the volume change behavior under zero-lateral displacement condition of Argentinean loessat natural moisture content and after inundations with a NAPL. Oedometer tests were run on undisturbed specimens of uncemented andcemented loess and silty sand under natural moisture content, and when flooded with water and NAPL. The results gave new insight onthe relevant mechanisms responsible of soil collapse, including the relative importance of soil suction, clay bridges expansion and saltdissolution at particles? contacts.