PhD Position Multi-Scale Characterisation and Modelling of Clay - Water Interactions

Job description 

Clays are key constituents of the subsurface, with critical roles in geotechnical engineering, environmental engineering, and geological processes. Their behaviour is governed by interactions between nanometre-sized clay minerals and pore water, yet these interactions remain poorly understood across scales. A defining feature of clays is their high specific surface area and charged surfaces, which cause water to adsorb strongly near mineral interfaces. This bound water exhibits altered properties—higher viscosity, lower mobility—than bulk water, influencing how clays deform over time under load.

This time-dependent (or "delayed") mechanical behaviour is a major uncertainty in predicting the long-term performance of clay-based barriers, foundations, and geological repositories. Despite decades of study, the fundamental coupling between mineral-fluid interactions and mechanical response is not well captured in current models. A core challenge is the lack of experimental tools that probe the relevant scales—from atomic to macroscopic—while replicating in-situ stress and hydration conditions.

This PhD project will address this gap through an integrated, multi-scale approach. The candidate will combine:

• Extensive characterisation of clay mineralogy and microstructure,
• NMR relaxometry to differentiate bound and mobile water populations,
• Mechanical testing under controlled hydration and loading, and
• Molecular dynamics simulations to resolve fluid-mineral interactions at the atomic scale.

These tools will be used in concert to unravel how water redistribution under stress affects the mechanical evolution of clays over time. A key goal is to identify the physicochemical parameters that govern delayed deformation and use these to inform constitutive models with improved predictive power.

This research will generate fundamental insights into the mechanics of clay–water systems, with broad relevance across geo-environmental engineering, subsurface engineering, and geotechnical engineering. By linking micro-scale processes to macro-scale behaviour, the project aims to set new standards in the modelling and interpretation of clay behaviour.

This position is part of the VIDI project "DELAY: the Dynamic Equilibrium of water in cLAYs and its impact on the time-dependent material behaviour" funded by the Dutch Research Council (NWO). The successful PhD candidate will join a dynamic research team at TU Delft, working on the multi-physics and multi-scale behaviour of clays with applications in geoenvironmental and geotechnical engineering. The position includes close collaboration with Prof. Jean-Michel Pereira and Prof. Laurent Brochard (École des Ponts ParisTech – Institut Polytechnique de Paris), including regular research visits. Accordingly, the PhD will be jointly supervised by Dr. Anne-Catherine Dieudonné, Prof. Jean-Michel Pereira and Prof. Laurent Brochard, offering a strong international and interdisciplinary environment for scientific and personal growth.

Job requirements 

Need-to-haves

• MSc degree in (applied) physics, material science, civil engineering, mechanical engineering, or related field
• Interest in multi-scale and multi-physics processes in geomaterials
• Motivation and attention to detail for conducting rigorous laboratory work
• Self-motivated, curiosity-driven, and open to communicating and cooperating with others
• Excellent written and oral communication skills in English (minimum requirement: TOEFL score of 100 or IELTS of 7.0 per sub-skill)

Nice-to-haves

• Experience in molecular dynamics simulations
• Experience in experimental testing (material characterisation)
• Dutch language knowledge, as this role includes collaboration with Dutch stakeholders and partners

TU Delft (Delft University of Technology) 

Delft University of Technology is built on strong foundations. As creators of the world-famous Dutch waterworks and pioneers in biotech, TU Delft is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society. For generations, our engineers have proven to be entrepreneurial problem-solvers, both in business and in a social context. 

At TU Delft we embrace diversity as one of our core values and we actively engage to be a university where you feel at home and can flourish. We value different perspectives and qualities. We believe this makes our work more innovative, the TU Delft community more vibrant and the world more just. Together, we imagine, invent and create solutions using technology to have a positive impact on a global scale. That is why we invite you to apply. Your application will receive fair consideration. 

Challenge. Change. Impact! 

Faculty of Civil Engineering and Geosciences 

The Faculty of Civil Engineering & Geosciences (CEG) is committed to outstanding international research and education in the field of civil engineering, applied earth sciences, traffic and transport, water technology, and delta technology. Our research feeds into our educational programmes and covers societal challenges such as climate change, energy transition, resource availability, urbanisation and clean water. Our research projects are conducted in close cooperation with a wide range of research institutions. CEG is convinced of the importance of open science and supports its scientists in integrating open science in their research practice. The Faculty of CEG comprises 28 research groups in the following seven departments: Materials Mechanics Management & Design, Engineering Structures, Geoscience and Engineering, Geoscience and Remote Sensing, Transport & Planning, Hydraulic Engineering and Water Management. 

Click here to go to the website of the Faculty of Civil Engineering & Geosciences.