Applications are invited for a PhD student at the University of Liège, to work on Unsaturated soil mechanics – Experimental and constitutive focus on desiccation cracking in fine-grained soils.
The PhD candidate will also take part in teaching activites related to soil and rock mechanics courses. The research and teaching assistant position is granted for a first term of two years, renewable for up to 2 further periods of 2 years.
The mechanics of desiccation cracking is a complex hydro-mechanical process, induced by soil drying in partially or totally strain-constrained conditions. Desiccation cracks may affect significantly the hydro-mechanical properties of fine-grained soils (strength weakening, increased compressibility, increased permeability), leading to potential geotechnical issues (landslide triggering, soil erosion, leakage of impermeable barrier, …).
In the framework of unsaturated soil mechanics, this study will investigate the conditions of desiccation cracks triggering, their propagation and their aperture evolution, from experimental and constitutive approaches. Suction control techniques, image analysis and tensile strength testing will be developed. A particular attention will be devoted to the determination of tensile strength criterion at various suctions, through innovative experimental developments
The experimental characteristics will then be encapsulated in constitutive laws and implemented in a finite element code. The numerical simulations will incorporate the modelling of water evaporation, the hydro-mechanical response of soil upon drying, the tensile strength criterion and the impact on the presence of the crack mechanical and hydraulic response of the ground. Finally, the methodology will be applied to study the conditions of occurrence of desiccation cracking in full-scale problems (earthfill dike, nuclear waste disposal gallery, landfill waste disposal, agricultural soils, …).
Requirements and application procedure
The position is open to graduated students (Master degree) in Civil Engineering, Geosciences or related disciplines.
Applicants should have a high level of proficiency in written and spoken English. The successful candidate is also expected to learn French during his first two years.
Applications must be sent by email to Prof. Frédéric Collin (F.Collin@uliege.be). It should include a motivation letter, a CV and a short abstract of the Master thesis. Please contact Prof. Frédéric Collin if you need more information.
Applications are welcome before 12th July 2021. The starting date is at the latest the 1st October 2021.