Concerns only the citizens of the People's Republic of China (Bourse du China Scholarship Counc[...]

enise; France; Sur place; EUR 24 000 - 30 000; Plein temps

Résumé du poste

A leading research institution in France is offering a PhD position focused on civil engineering. The research will involve utilizing recycled materials from demolished concrete and developing numerical models to simulate hydration processes. Candidates should possess relevant qualifications and experience in numerical modeling and materials testing. This role is critical for advancing sustainable construction methods.

Qualifications

• Candidate must develop simulations of hydration processes.
• Experience with numerical modeling and materials testing is vital.
• Knowledge in heat and mass transfer phenomena is required.

Responsabilités

• Conduct numerical modeling and validate results through experimental studies.
• Develop a 3D matrix for hydration simulations.
• Perform thermal and mechanical characterization tests.

Formation

PhD

Outils

CEMHYD3D

Cast3M

Description du poste

Organisation/Company enise Research Field Engineering » Civil engineering Researcher Profile First Stage Researcher (R1) Positions PhD Positions Country France Application Deadline 1 Jun 2026 - 01:00 (Europe/Prague) Type of Contract Temporary Job Status Full-time Offer Starting Date 1 Sep 2026 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

The use of recycled materials from demolished concrete contributes to limit landfill and the systematic use of natural resources. Using recycled cement from the deconstruction concrete is an extension of this approach. When used as a partial substitution for cement in cementitious materials, it may also be a solution to reduce the environmental impact of these materials. Recent studies on utilization of CO2 in concrete production have been focused on the CO2 treatment on recycled concrete cement paste[1–3]. In addition to the manufacture of low CO2-emission binders for cement-based materials, works have been done on combining CO2 capture with preparation of cement-based materials, carbonation treatment in cement based material productions[4]. Carbonation treatment or carbonation curing for concrete materials is believed can give not only an efficient way to capture and utilize CO2, but also a way to accelerate the strength development, shorten the curing time, and improve the performance of cement-based materials. The high temperature action on recycled concrete can lead to the spalling and cracking phenomena[5]. This thermal sensitivity could be the product of vapour pressure build-up mechanisms[6]and/or the restrained thermal dilatation mechanisms[7]. Furthermore, the parameters such as water content, porosity, permeability, type of aggregates, heating rate, etc. have an influence on concrete thermal stability[8]. Some experimental studies showed that the carbonated cement matrix could better resist to fire than the ordinary concretes[9,10], however no numerical simulation has been carried out to confirm.

Description of the work:

The PhD thesis includes two phases of numerical modelling and the validation of numerical results by an experimental study on material level. Firstly, the development of hydration processes including the carbonated matrix in three-dimensional arrangement of particles will be simulated with the help of CEMHYD3D (NIST): - creation of 3D matrix basing on the granular distribution, placing randomly in a finite cubic volume single phase clinker carbonated particles; - transformation of monophasic phases to multiphasic; - hydration execution as a cycle of dissolution, diffusion and precipitation. Secondly, the created numerical model will be introduced in a finite element method software as Cast3M (macroscopic approach) in order to deepen the understanding of the coupled heat and mass transfer phenomena within the carbonated recycled concrete microstructure at high temperature. After the temperature, pressure and mass loss simulating, the quantified fluid influence of thermal action phenomenon on cement based material microstructure will be generated. The PhD thesis will be validated with physical, thermal and mechanical characterization tests in order to confirmer the numerical simulations and draw relevant conclusions.

References:

[1] J. Zhang, C. Shi, Y. Li, X. Pan, C.S. Poon, Z. Xie, Influence of carbonated recycled concrete aggregate on properties of cement mortar, Constr. Build. Mater. 98 (2015) 1–7. doi:10.1016/j.conbuildmat.2015.08.087.

[2] B.J. Zhan, C.S. Poon, C.J. Shi, Materials characteristics affecting CO2 curing of concrete blocks containing recycled aggregates, Cem. Concr. Compos. 67 (2016) 50–59. doi:10.1016/j.cemconcomp.2015.12.003.

[3] B. Zhan, C. Poon, C. Shi, CO2 curing for improving the properties of concrete blocks containing recycled aggregates, Cem. Concr. Compos. 42 (2013) 1–8. doi:10.1016/j.cemconcomp.2013.04.013.

[4] M. Fernández Bertos, S.J.R. Simons, C.D. Hills, P.J. Carey, A review of accelerated carbonation technology in the treatment of cement-based materials and sequestration of CO2, J. Hazard. Mater. 112 (2004) 193–205. doi:10.1016/j.jhazmat.2004.04.019.