Informations générales
Intitulé de l'offre : Thèse (M/F) : Shrinkage and rheology of early age cementitious pastes (H/F)
Référence : UMR7504-PASHEB-006
Nombre de Postes : 1
Lieu de travail : STRASBOURG
Date de publication : mercredi 13 août 2025
Type de contrat : CDD Doctorant
Durée du contrat : 36 mois
Date de début de la thèse : 1 octobre 2025
Quotité de travail : Complet
Rémunération : 2200 gross monthly
Section(s) CN : 05 - Matière condensée : organisation et dynamique
Description du sujet de thèse
The aim of this thesis is to study the evolution of the mechanical properties of cementitious pastes at an early age. Their macroscopic strength is based on the cohesion created by the precipitation of hydrates, mainly calcium silicate hydrates (C-S-H), which occurs as soon as the cement comes into contact with water and dissolves. Two stages can be distinguished: (i) the formation of a network connected by surface interactions between particles partially covered with a few early C-S-H nanoparticles, and (ii) the increase in adhesive forces, linked to the growth of C-S-H precipitation. Similar mechanisms appear in formulations in which cement is partially or totally replaced by calcium-rich precursors (e.g., slag), forming C-A-S-H-type hydrates. We will use rheology and multiple light scattering to observe the structuring and dynamics of the paste. We will focus in particular on the local dynamics induced by the existence of shrinkage in these systems, and will seek to determine whether precursors of microfractures can be measured at very early ages.
Contexte de travail
The Strasbourg Institute of Physics and Chemistry of Materials (IPCMS-UMR7504) is a joint research unit bringing together the CNRS (CNRS-Physics & CNRS-Chemistry) and the University of Strasbourg. The Institute has a large range of instruments for the manufacture and characterization of materials at all scales. The IPCMS currently employs 240 people, including around 80 researchers and teacher-researchers and 60 technical staff. The PhD student (M/F) will be attached to the Doctoral School of Physics and Physical Chemistry (ED182). Their thesis work will be carried out at IPCMS, within the Optics and Nanophotonics Department, in the Biophysics and Soft Matter team. The position is in a sector subject to scientific and technical potential protection (PPST).
Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.
Contraintes et risques
Laboratory work in compliance with health and safety guidelines and wearing appropriate personal protective equipment.