PhD Student in Materials / Civil Engineering (M/F)

Job Description

Thesis Subject

Building on the MATARUN project, this research will focus on the characterization of a wide range of formulations developed using different types of local soils, with the aim of establishing a multi-factor model linking the intrinsic properties of soils, formulation parameters, and the overall expected performance of the resulting material.
The experimental and numerical components will form the core of the research and will draw on the complementary expertise of the two partner laboratories. The work will be structured around two main scientific components:
(1) First component – Modelling the properties of Compressed Earth Blocks (CEBs) from experimental data
The results obtained from previous experimental tasks (T1a & T1b), complemented by the extensive research available in the literature and within the CNRS JRP AI4EB project, will form a structured database. This database will link, as input variables, soil types and formulations (composition, binder type, fibre content, degree of compaction, particle-size distribution) to measured block-scale performance indicators (thermo-hygro-mechanical properties).
This database will be used to identify a reliable and computationally efficient predictive model capable of estimating CEB properties based on the composition of Réunion Island soils and the type of stabilizer considered. Artificial intelligence methods (supervised and unsupervised learning, generative models) will be employed to investigate nonlinear interactions between formulation variables and observed performance.
(2) Second component – Numerical modelling of hygrothermal behaviour at building scale
The outputs of Model 1 (the hygrothermal properties of CEBs) will then be integrated, together with weather files representative of the main microclimates of Réunion Island (warm coastal areas, temperate mid-altitude areas, and cool high-altitude areas), into a numerical experimental design developed using EnergyPlus.
This model will be used to assess the hygrothermal behaviour of the building and occupant comfort at single-zone scale, by simulating interactions between material properties and indoor air temperature / relative humidity (T_air, RH_air). This stage will establish a hierarchical relationship between material properties and the overall thermal behaviour of the single-zone building, thereby providing a link between observations under real-site conditions (T2) and simulated operating conditions.
A numerical database will be generated from this experimental design and analysed using generative artificial intelligence tools to simulate building behaviour based on CEB properties and climate conditions. Sensitivity analyses and multi-objective optimization (performance, durability, environmental footprint) may be implemented to improve the robustness and transferability of the model.
The final model will provide predictive and context-specific formulations adapted to the soil type, microclimate, and manufacturing process under consideration.

Your Work Environment

GeM is a Joint Research Unit involving Centrale Nantes, the University of Nantes, and the CNRS. Established in 2004, the laboratory comprises approximately 240 staff members distributed across three sites in Nantes and Saint-Nazaire. Its objective is to bring together—within a single laboratory—the full range of expertise found in the Nantes–Saint-Nazaire metropolitan area regarding civil engineering, materials and process mechanics, and structural mechanics modeling and simulation.
GeM is deeply committed to research-based training, hosting around one hundred doctoral students and managing several Master's programs. The research activities of its nine Thematic Research Units (UTR) are structured around the Materials–Processes–Structures triad. In-house expertise encompasses experimental techniques, modeling, and numerical simulation.
This PhD thesis will be conducted within the framework of the ASTER project (Architecture and Tropical Soils through Experimentation in Réunion), funded under the LORIZON 2026 call for projects. The project aims to reduce the importation of construction materials to Réunion Island by promoting the use of locally available materials.
The ASTER project builds on the complementary expertise of the GeM Laboratory (Nantes Université, ECN, UMR 6183) and the PIMENT Laboratory (Université de La Réunion).
GeM provides recognized expertise in physicochemical and microstructural characterization, in order to assess the mechanical behaviour and durability of construction materials. The laboratory also has established expertise in modelling methods, including multiscale approaches based on homogenization techniques (ANR projects Demcom and MHygroTer) and artificial intelligence methods (CNRS JRP AI4EB project).
The PIMENT Laboratory, for its part, has extensive experience in tropical climatic conditions and Réunion Island volcanic soils. For several years, it has developed applied research on the thermo-hygro-mechanical (THM) behaviour of building envelopes under real-world conditions and on occupant comfort.
The project will be co-supervised by S. Bonnet and B. Malet-Damour, whose complementary expertise converges on the valorisation of geo-sourced materials.
This PhD project is strongly supported by Action Logement, with the aim of addressing the housing crisis in Réunion Island through the use of locally available natural materials and co-products.
The PhD student will participate in international conferences related to the research topic and will publish research articles in peer-reviewed scientific journals.
The equipment and facilities of both laboratories involved in the project will be made available to the recruited candidate to carry out the research work. Travel and material expenses will be covered by the laboratories.

Constraints and risks

The recruited candidate must be willing to travel between the two research sites.

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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