Consultation des offres
PhDproposal:«Earth structure vulnerability with respect hydric conditions" CDD
Noémie Prime (LOCIE)
The ongoing ecological crises impose inevitable changes in society’s organization and development. Construction field being very one of the highest energy and mineral raw-material consuming, new processes are being intensively investigated to reduce building environmental impact.
In this context, we are interested in the potential of raw earth material for both construction and renovation. Indeed, this material requires little transport energy (it is available on many building sites), little manufacturing one (no heating at 1500 °C like for cement), and therefore has low carbon emission. In addition, it is fully recyclable and thus fuels circular economy. Raw earth has, however, a significant disadvantage: its sensitivity to liquid water has a direct effect on its consistency. Indeed, it can pass from fragile to plastic state, and therefore undergo significant decrease of rigidity or strength. This behaviour is being investigated at the material scale and for a particular earth at LOCIE (El Hajjar et al.k 2018) through unsaturated soil mechanics approach. However, several questions remain open:
- How can the coupled behaviour be experimentally quantified at the larger scale (structural element as pile or wall at the scale ½) and for non uniform hydric states? A particular focus will concern the effect of hydric cycles on the behaviour. Another important point would be to compare 2 different earths.
- Would it be possible to numerically predict this effect of water ingress on the mechanical behaviour at a large scale? The main challenge of such a model would be to adapt soil mechanics models for buildings.
- Finally, would it be possible to apply the experimental and numerical approach to a real existing building? The objective aimed is to determine whether the selected construction would be far or not from instable state.
The student will be encouraged to valorize his/her work by oral presentation in national/international congresses, and by the redaction of scientific publications.
Contact possible until may 15th: please send a cover letter, a CV, a lists of courses attended (with grades obtained), and names and contact details of two reference
- Mécanique des sols