MICROSTRUCTURAL MODELLING STATE OF THE ART AND PERSPECTIVES

Author(s): Karen L. Scrivener
Book Title: RILEM International Symposium on Concrete Modelling - CONMOD 2014
Editors: Kefei Li, Peiyu Yan and Rongwei Yang
ISBN: 978-2-35158-139-1
e-ISBN: 978-2-35158-140-7
Publisher: RILEM Publications SARL
Publication year: 2015
Pages: 3
Total Pages: 1
Language: English

Abstract: Abstract only
This presentation will review where we are on microstructural modelling. Early approaches were based on codifying empirical data. With the increase in computing power and the development of new algorithms, it is now possible, in the μic platform developed at EPFL, to deal with many of millions of particles and generate microstructures based on mechanisms. When this is done we find that many of the mechanisms assumed to govern hydration - for example diffusion through layers of hydration products – are in fact incorrect. Most critically new knowledge which is emerging about the structure of the main calcium silicate hydrate (C-S-H) phase poses considerable challenges. C-S-H grows first as “needles” which nucleate on solid surfaces (not only alite grains) these grow to a critical length. Thereafter the rate of hydration drastically slows and the C-S-H product densifies. This early
“roughness” of C-S-H presents new problems in terms of resolution to represent the pore structure.

We are also acquiring new knowledge about the way supplementary cementitious materials react and modify the pore space over the longer term.

Finally we are advancing in our understanding of how the changes in the microstructure can be linked both to mechanical and transport properties.

Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00