Physics of Frost Heaving

When a soil is subject to low temperatures, the freezing of water can lead to an upward forces and the deformation of the soil with the growth of ice. This phenomena, called frost heaving can lead to catastrophic destruction of roads or buildings in cold regions as shown in figure above. The most obvious explanation for this phenomenon comes from the fact that water expands by about 9% when 
it turns into ice. If the water completely fills the porous soil and starts freezing, the ice will subsequently apply pressure on the soil leading to its deformation. This explanation falls short however, as soils are generally not fully saturated and one would then expect the ice to be able to grow where there is room to expand. It is believed that the build-up of ice happens largely because 
water in the unfrozen soil below gets drawn up into the freezing zone and attaches itself to the existing frost crystals to form ever thickening layers of ice. The phenomenon is also known as ice segregation or ice lense formation. The cause of frost heave is therefore somewhat not fully understood, and a lot of questions remain unanswered.

During this master project, you will experimentally investigate the mechanism of phase transition of water to ice in granular materials when partially saturated with water. The objective is to understandwhat the conditions for ice lenses formation are. For that, you will design an experimental set-up similar to a Hele-Shaw cell to study a model soil under freezing conditions. Several parameters will beinvestigated such as: 

- the saturation of the soil,
- its physical properties (hydrophilicity, compaction and poydispersity)
- the freezing temperature