Abstract:
Naturally frozen soils, including permafrost and seasonally frozen soils, cover around 20% of the land surface on Earth. In recent decades, these regions have been subjected to warming, affecting the equilibrium conditions of frozen soils and causing significant ground perturbations compared to other regions. Thawing permafrost critically impacts the stability of infrastructures in inhabited regions or areas exploited for mineral and energy resources. This study aims to investigate the behavior of frozen soils under mechanical loading and freezing/thawing processes using laboratory soil microstructural observations. The tests will be performed on sandy soils with various fine contents. The research is structured into three main tasks:
- Conducting frost heave tests combined with Magnetic Resonance Imaging technique (MRI).
- Investigating the thawing characteristics of frozen soils using Nuclear Magnetic Resonance (NMR) relaxometry.
- Examining microstructural changes at the particle scale during thawing using an X-ray microtomography (XRμCT)-based triaxial apparatus. 3D image processing of the XRμCT tests will be performed to quantitatively investigate the behavior of frozen soils using volumetric digital image correlation.
In this seminar, I will present the main aspects of my PhD research, the progress of each task, and the results obtained from the frost heave tests conducted so far.
This PhD thesis is part of REFROZEN project, a collaboration between Ecole nationale des ponts et chaussées (France) and RWTH Aachen University (Germany).
Short bio:
Christelle Tabbiche is a civil enginee. She completed a research master’s degree (MSROE) at École Nationale des Ponts et Chaussées. She is currently working on a PhD thesis at the Navier Laboratory in collaboration with three teams: Géotechnique, RMP, and Multi-Échelle. Her research focuses on frozen soils, and since the start of my PhD, I have developed a strong interest in this field.
