MSCA COFUND PhD@Tec21 - PhD position in Geomechanics: Multiscale modelling of swelling clays: from water and ions at the nanoscale to thermo-hydro-mechanical behaviour

id="offer-description" class="ecl-u-type-heading-2 ecl-u-mt-none ecl-u-mb-l">Offer Description Context and work environment . Clay materials combine low permeability, high plasticity and strong sensitivity to moisture and temperature. They play a key role in the design of foundations, earth structures, energy geostructures, energy storage systems and engineered barriers (e.g. underground waste storage), being subjected to thermo-mechanical loading. Their behaviour emerges from coupled processes across multiple scales, ranging from molecular interactions between particles to macroscopic mechanical response. Among clay minerals, smectites are the most challenging to model. Their typical swelling behaviour originates from the interplay between interlayer water, ions and charged surfaces. Thermal loading induces counter-intuitive, non-monotonic changes in swelling pressure that existing mesoscale models fail to capture. The objective of this PhD is to understand how hydration-state transitions in smectite clays, driven by water and ions confined at the nanoscale, control the swelling pressure response under thermal and mechanical loading, including its non-monotonic temperature dependence observed experimentally. By coupling all-atom molecular simulations, DLVO calculations and coarse-grained molecular dynamics, the PhD will bridge molecular-scale mechanisms and macroscopic behaviour. The transferability of the results to other interface-driven geomaterials, such as unsaturated s