Are some phobias good? Examining hydro-mechanical relationships in hydrophobic soils

Soil water repellency naturally arises due to the deposition of plant oils or humic substances or after severe heating episodes, for example wildfires. Artificial treatments can also be used to render soils permanently hydrophobic. Such treatment might be desirable to deter infiltration, for example in engineered cover systems where waste exposure to water may result in severe contamination of the surrounding landscape.

It is well understood that microscopic interactions between water menisci and soil particles govern the macroscopic mechanical behaviour of unsaturated soils. However, how water repellency affects those interactions is largely unknown. Successfully accounting for the effect of repellency on soil hydro-mechanical behaviour could yield significant benefits to geotechnical design.

This project will exploit state-of-the-art experimental techniques to examine the evolution of water-repellent soil hydro-mechanical behaviour on the microstructural and macrostructural scale. The project will take advantage of the long-term strong collaborative relationships between leading UK universities studying unsaturated soil behaviour to deliver an engaging and rewarding PhD experience.