Carbonation, decalcification and recalcification of Calcium-Silicate-Hydrate

Promoter

Cizer Özlem, (Katholieke Universiteit Leuven (KULeuven)), ozlem.cizer@kuleuven.be

SCK•CEN Mentor

Phung Quoc Tri, qphung@sckcen.be, +32 (0)14 33 32 40

Expert group

R&D Disposal

SCK•CEN Co-mentor

Maes Norbert , nmaes@sckcen.be , +32 (0)14 33 32 35

Short project description

Calcium-Silicate-Hydrate (C-S-H) – xCaO.ySiO2.zH2O – is essentially the glue of a cement matrix which consists roughly 50% of C-S-H. Although cement-based materials are complex multiphase materials, C-S-H is the dominant phase controlling its performance. Knowledge of the exact nature of C-S-H, its nano/microstructure and degradation mechanisms is essential to improve significantly the ability to predict and control the performance of cementitious materials, more particularly those used for the  encapsulation of radioactive wastes and geological disposal.   

This PhD project aims at performing a comprehensive experimental study to assess the nano level of C-S-H to fundamentally understand the changes in structure and chemical composition of C-S-H under chemical degradation by carbonation, leaching and recalcification. Various types of C-S-H (real and synthetic) with different Ca/Si ratios will be subjected to a number of degradation conditions to understand the C-S-H degradation mechanism.  A variety of characterization techniques will be used to quantify the change in chemistry and structure of C-S-H, which is combined with modelling approach in order to explore the effect of different degradation mechanisms, this may lead to engineering of cementitious materials with highly durable C-S-H.      

The minimum diploma level of the candidate needs to be

Master of sciences , Master of sciences in engineering

The candidate needs to have a background in

Chemistry , Civil engineering, Construction material engineering

Estimated duration

4 years
Before applying, please consult the guidelines for application for PhD.