Conferences - Seminars
CESS Seminar: Multiscale methods for predicting the long‐term creep deflection of concrete structures
By Prof. Luca Sorelli, professor at Université Laval (Quebec), director of the laboratory on Multiscale Characterization of Construction Materials (MCCM)
Recent works have shown that the several national codes provide alarming unsatisfactory prediction of the long-term deflection of concrete bridges being monitors in USA. The crux of the problem is to predict long-term (e.g., 30-50 years) deflection from laboratory short-term tests (e.g., over few years, if not months). Can we predict the long-term deflection of concrete structures by laboratory short-term tests?
To answer, this work takes a different approach to characterize concrete creep by explicitly considering the creep mechanisms that are at stake at the microstructure scale. Thanks to the tiny-probed volume, nano- and micro-indentation can quickly access to the long-term creep properties. This talk presents latest results on the effect of water, which allows speculating that the rapid equilibrium between capillary and disjoining forces affects the creep mechanism between the C-S-H sheets at the smaller scale. After modeling the dual creep/relaxation mechanism of creep by viscoelastic theory, the creep compliance function are up-scaled by micromechanics to predict the long-term creep. Finally, the up-scaled creep curve for mortar and concrete is compared against experimental results, the logarithmic basic creep formula of 2010 fib model code and the well-recognized Bazant B4 model.
Dr. Luca Sorelli is professor at Université Laval (Quebec) and director of the laboratory on Multiscale Characterization of Construction Materials (MCCM). He has worked at different international research groups, such as, the durability division at IFSTTAR (Paris), the civil engineering department at MIT (Cambridge) and the LCR research center of LafargeHolcim (Saint-Quentin-Fallavier). Dr. Sorelli is member of the industrial consortium CIRCERB on eco-responsible structure. The vision of his research group is to develop efficient material-to-structure approach for fostering structural applications of new composite materials, which can fulfil the needs of today society and address the environmental challenges.
Organization Profs. Brice Lecampion & Alexandre Alahi
Contact Prof. Eugen Brühwiler
Accessibility Informed public
This event is internal